CSS

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Posted by bender 04/04/2009 @ 17:09

Tags : css, web design, internet, technology, national security agency, intelligence agencies, government, politics

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Creating Pure CSS Templates in Joomla! - informIT
Specifically, you will create a template that uses Cascading Style Sheets (CSS) to produce a layout—without using tables. This chapter walks through the steps of creating a Joomla template. Specifically, you will create a template that uses Cascading...
RealNetworks claims CSS license lets it copy DVDs. Sues studios - Register
It says it has a license to use CSS decryption which it obtained legally, and therefore its RealDVD copying software is not only legal, but attempts by the studios to block it amount to anti-trust. It will be interesting to see if a court agrees....
Mozilla launches Jetpack; Will add-ons be Firefox's secret sauce? - ZDNet
The general idea for Jetpack, which is in an early stage, is to develop browser add-ons with common technologies such as HTML, CSS and JavaScript. Jetpack is Mozilla's attempt to take its 8000 developers—and 12000 add-ons they have produced—to another...
Cajuns Face MT on CST, CSS At 2 pm - Louisiana's Ragin' Cajuns Athletics
The 2 pm championship game originally scheduled for Saturday will still be broadcast on CST and CSS, but will now instead feature the Ragin' Cajuns and Blue Raiders in their third-round elimination game. The championship game has been postponed until...
Gordon Strachan's career at Celtic - BBC Sport
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience....
CSS loses $5.4M in fiscal 4Q - Bizjournals.com
CSS Industries Inc., which supplies gift wrap and other seasonal products to retailers, said it narrowed its fourth-quarter loss to $5.4 million. The deficit, equal to 57 cents a share, compared to a loss of $6.6 million, or 63 cents, a year earlier....
CS Sfaxien win fourth Tunisian Cup - magharebia.com
USM launched several attacks, but the most important scoring opportunity was for CSS when Dominique Da Silva took advantage of the confusion between one of USM's defenders and the goalkeeper, but the ball hit the bar. Da Silva also passed up the...
Senior UI Designer - Gamasutra
Work with the Art Director and Game Design team to design user interface from websites to in-game, using industry standard tools (HTML/CSS, XUI, Adobe Flash, Adobe Photoshop or MS Expression Blend as well as proprietary in engine tools)....
XHTML and CSS Improvements - MSDN Magazine
This article, Part 3, will focus on using XHTML and Cascading Style Sheets (CSS) to improve the layout and visual appeal of the site. ASP.NET Web Forms goes out of its way to protect you from the big, bad old Web. A world of HTML, CSS, and JavaScript...
CSS/ESPN Reaches Agreement To Broadcast SEC - Today's THV
Comcast / Charter Sports Southeast (CSS), the regional sports channel focusing on college sports in the southeast, announced today it has reached a five-year agreement with ESPN to televise live Southeastern Conference (SEC) content including a minimum...

CSS Virginia

CSS Virginia

CSS Virginia was a steam-powered battery design ironclad warship of the Confederate States Navy during the American Civil War (built using the remains of the scuttled USS Merrimack).

She was one of the participants in the Battle of Hampton Roads in March 1862 opposite the USS Monitor. The battle is chiefly significant in naval history as the first battle between two ironclads.

Ironclads were only a recent innovation, starting with the 1854 steam-powered ironclad battery Lave, which was designed for coastal warfare and had a speed of 4 knots (7.4 km/h), with a crew of 282 men. Throughout the war, the Confederacy built many ironclad steam-powered batteries, and like the CSS Virginia, they were not designed to be ocean cruisers. Due to the success of the CSS Virginia, the CS Navy tried to procure turreted ironclad cruisers, but only succeeded in procuring one ironclad frigate, the CSS Stonewall, which arrived too late to make an impact in the war.

When the Commonwealth of Virginia seceded from the Union in 1861, one of the important federal military bases threatened was Gosport Shipyard (now Norfolk Naval Shipyard) in Portsmouth, Virginia. Accordingly, the order was sent to destroy the base rather than allow it to fall into Confederate hands. Unfortunately for the Union, the execution of these orders was bungled. The steam frigate USS Merrimack sank before she completely burned. When the Confederate government took possession of the yard, the hulk of the Merrimack was raised and moved pierside to clear the main channel of the Elizabeth River of the obstruction. About two months later, Confederate Navy Leutenants John Brooke and John Porter surveyed the hull and found the running gear satisfactory to base conversion of the hull to an ironclad ram.

Rebuilt under the supervision of Captain French Forrest, the new ship was named Virginia. The burned hull timbers were cut down to the waterline, and a new deck and armored casemate (fortress) were added. The deck was four inch (102 mm)-thick iron. The casemate was built up of 24" of oak and pine in several layers, topped with two 2-inch (51 mm) layers of iron plating oriented perpendicular to each other, and angled to deflect shot hits. The battery consisted of four single-banded Brooke rifles and six nine-inch (229 mm) Dahlgren smoothbore shell guns. Two of the rifles, bow and stern pivots, were seven-inch (178 mm) , of 14,500 pounds; the other two were 6.4 inch (32 pound calibre) of 9000 pounds, one on each broadside. The nine-inch (229 mm) gun on each side nearest the furnaces was fitted for firing hot shot. A few nine-inch (229 mm) shot with extra windage (slightly smaller diameter) were cast for hot shot. No other solid shot were on board during the fight. As Virginia’s designers had heard of plans by the North to build an ironclad, and figuring her guns would be unable to harm such a ship, they equipped her with a ram— at that time an anachronism in a warship. Merrimack's engines, now part of Virginia, had not been in good working order, and the salty Elizabeth River water and addition of tons of iron armor and ballast did not improve the situation.

The commanding officer, Flag Officer Franklin Buchanan, arrived to take command only a few days before sailing. The ship was placed in commission and equipped by the executive officer, Catesby ap R. Jones.

The Battle of Hampton Roads began on March 8, 1862 when Virginia sortied. Despite an all-out effort to complete her, the ship still had workmen on board when she sailed. Supported by Raleigh and Beaufort, and accompanied by Patrick Henry, Jamestown, and Teaser, Virginia took on the blockading fleet.

The first ship engaged, USS Cumberland, was sunk after being rammed. However, in sinking, Cumberland broke off Virginia's ram. Seeing what happened to Cumberland, the captain of USS Congress ordered his ship grounded in shallow water. Congress and Virginia traded fire for an hour, after which the badly-damaged Congress surrendered. While the surviving crewmen of Congress were being ferried off the ship, a Union battery on the north shore opened fire on Virginia. In retaliation, the captain of Virginia ordered to fire upon the surrendered Congress with red-hot shot, to set her ablaze.

Virginia did not emerge from the battle unscathed. Shot from Cumberland, Congress, and the shore-based Union troops had riddled her smokestack, reducing her already low speed. Two of her guns were out of order, and a number of armor plates had been loosened. Even so, her captain attacked USS Minnesota, which had run aground on a sandbank trying to escape Virginia. However, because of her deep draft, Virginia was unable to do significant damage. It being late in the day, Virginia left with the expectation of returning the next day and completing the destruction of the Union blockaders.

Later that night, USS Monitor arrived at Union-held Fort Monroe, rushed to Hampton Roads in hopes of protecting the Union force and preventing Virginia from threatening Union cities.

The next day, on March 9, 1862, the world's first battle between ironclads took place. The smaller, nimbler Monitor was able to outmaneuver Virginia, but neither ship proved able to do significant damage, despite numerous hits. Monitor was much closer to the water, and thus much harder to hit by the Virginia's guns, but vulnerable to ramming and boarding. Finally, Monitor retreated. This was because the captain of the Monitor was hit by gunpowder in his eyes while looking through the pilothouse's peepholes, which caused Monitor to haul off. The Monitor had retreated off into the shoals and remained there, and so the battle was a draw. The captain of Virginia, Lieutenant Catesby ap Roger Jones, CSN received the advice from his pilots to take the midnight high tide to depart back over the bar toward the CS Navy base at Norfolk until noon of the next day. Lieutenant Jones wanted, instead, to re-attack, but to "turn the ship and fight the starboard gun, was impossible, for heading up stream on a strong flood-tide, she would have been wholly unmanageable." The pilots emphasized that the Virginia had "nearly three miles to run to the bar" and that she could not remain and "take the ground on a falling tide." So to prevent getting stuck, Lieutenant Jones called off the battle and moved back toward harbor.

In the following nine weeks, the crew of the Virginia were unsuccessful in their attempts to lure the Monitor out of the shallows. The Virginia made several sorties back over to Hampton Roads hoping to draw Monitor into battle. Monitor, however, was under orders not to engage. Eventually the Confederate Navy sent Lieutenant Joseph Nicholson Barney in command of the CSS Jamestown, along with the Virginia and five other ships in full view of the Union squadron, enticing them to fight. When it became clear that the US Navy ships were unwilling to fight, the CS Navy squadron moved in and captured three merchant ships, the brigs Marcus and Sabout and the schooner Catherine T. Dix. Their flags were then hoisted "Union-side down" to further taunt the US Navy into a fight, as they were towed back to Norfolk, with the help of the CSS Raleigh.

Neither ironclad was ever to fight again. On May 10, 1862, advancing Union troops occupied Norfolk. Virginia was unable to retreat further up the James River due to her deep draft, and since she was a steam-powered battery and not a cruiser, she was not seaworthy enough to enter the ocean. Without a home port, Virginia was ordered blown up to keep her from being captured. This task fell to Lieutenant Jones, the last man to leave CSS Virginia after all of her guns had been safely removed and carried to the CS Marine Corps base and fortifications at Drewy's Bluff to fight again. Early on the morning of May 11, 1862, off Craney Island, fire reached her magazine and she was destroyed by a great explosion.

Later that same year, despite being an armored raft designed for riverine warfare, the US Navy attempted to tow the USS Monitor out into the Atlantic Ocean and past the ship graveyard of Cape Hatteras, North Carolina, where the Monitor was added to the collection.

The name of the warship which served the Confederacy in the famous Battle of Hampton Roads has become a source of confusion, which continues to the present day.

When she was first commissioned into the United States Navy in 1856, her name was Merrimack, with the K. The name derived from the Merrimack River near where she was built. She was the second ship of the U.S. Navy to be named for the Merrimack River, which is formed by the junction of the Pemigewasset and Winnipesaukee Rivers at Franklin, New Hampshire. The Merrimack flows south across New Hampshire, and then eastward across northeastern Massachusetts before emptying in the Atlantic at Newburyport, Massachusetts.

The Confederacy bestowed the name Virginia on her when she was raised, restored, and outfitted as an ironclad warship, but the Union preferred to call the Confederate ironclad warship by either its earlier name, "Merrimack", or by the nickname, "The Monster".

Perhaps because the Union won the Civil War, the history of the United States generally records the Union version. In the aftermath of the battle, the names Virginia and Merrimack were used equally by both sides, as attested by the newspapers and correspondence of the day. Some Navy reports and pre-1900 historians misspelled the name as "Merrimac," which is actually an unrelated ship. Hence "the Battle of the Monitor and the Merrimac". Both spellings are still in use in the Hampton Roads area.

In 1907, an armor plate from the ship was melted down and used in the casting of the Pokahuntas Bell for the Jamestown Exposition.

The name of the Monitor-Merrimac Memorial Bridge-Tunnel, built in Hampton Roads in the general vicinity of the famous engagement, with both Virginia and federal funds, also reflects the more recent version.

Should periodic modern efforts to recover more of the Confederate vessel from the depths of Hampton Roads prove successful, it is unclear what name will be applied to the remains.

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CSS (band)

CSS performing at Rock en Seine

CSS is a Brazilian band from São Paulo, whose songs have an electroclash sound, but they also play indie rock and synthpop songs. The band was labeled as part of the explosion of the New Rave scene. Their songs are in both English and Portuguese. CSS is an acronym for Cansei de Ser Sexy (pronounced ), literally "I got tired of being sexy" in Portuguese.

CSS formed in September 2003, consisting of a group of friends. Their name was taken from a reported quote by Beyoncé, who allegedly declared that she was "tired of being sexy".

The band first achieved notoriety through the Internet. Some of its members, like Adriano Cintra, had been previously known in São Paulo's underground club scene, but not outside of the local alternative subculture. Others, like Lovefoxxx, were owners of popular fotolog and flickr pages. Their collective band fotolog also gained popularity and their songs were frequently downloaded from Trama Virtual's website (a Brazilian website loosely similar to MySpace Music). Trama Virtual invested heavily in the band, inviting a series of Brazilian and British journalists to report on them. Articles were printed in several Brazilian magazines and the British newspaper The Guardian, whose reporter, Peter Culshaw, was invited to see the band playing just before their signing for the debut, at a club in São Paulo. He predicted that they "could be the biggest band ever to come out of South America". Several songs by CSS were featured in mainstream media: "Meeting Paris Hilton" was featured in the Latin American broadcasting of The Simple Life, "Superafim" was used in the Brazilian version of the Big Brother reality show, and "Computer Heat" was used in the South American version of the game The Sims 2: Nightlife, including a version in Simlish. Still without a record deal, they released two independent EPs in 2004, and played that year at TIM Festival.

In 2005, they signed with the Trama Virtual label, and in October their first album was released in Brazil, along with an 7-track EP that was sold at concerts. A limited edition version of the album had a CD-R included, so that the buyer could burn a copy of the album onto the CD-R to give away as a gift. In Brazil the album has reportedly sold 5,000 copies to date, but neither the album nor the singles have reached charts. Two music videos were also released: "Off The Hook" and "Alala". "Off the Hook" was directed by guitar player Ana Rezende, and filmed at the home of band members Carolina Parra and Adriano Cintra, where CSS recorded most of their songs.

In the beginning of 2006, CSS signed with Sub Pop to release their international debut album. The first single, released on 6 June, was "Let's Make Love and Listen to Death From Above", with an accompanying video directed by Cat Solen. In July, along with DJ Diplo and funk group Bonde do Rolê, they began their first international tour.

CSS sold as many as 60,000 copies in the US and Europe up to February 2007 (according to journalist Lucio Ribeiro in Folha de São Paulo).

They played at various festivals across Europe in the summer of 2007, and were due to play Lollapalooza on 4 August 2007 but they were held behind by United Airlines at New York Airport and missed it. They did arrive in time for their performance at Virgin Festival in Baltimore the next day.

CSS caught an unlikely break when their song "Music Is My Hot Hot Sex" was used in a worldwide television commercial by Apple Inc. for the iPod. An 18-year-old British student, Nick Haley, used the song in a homemade 30-second commercial for the iPod Touch that he created and then posted on the video sharing site YouTube on 11 September 2007. Creative executives from Apple's advertising agency, TBWA\Chiat\Day, saw Haley's creation, contacted him, and enlisted him to remake it as a broadcast version. The spot began airing in the U.S. on 28 October 2007, and later in Japan and Europe. Due to the song's exposure in the US, it hit #63 on the Billboard Hot 100, becoming the highest charting single by a Brazilian band in the history of the chart. Coincidentally, the same song had been used in a promotion for the competing Zune media player a year prior. In March 2008, the music video for the song amassed over 112 million views on YouTube, making it the most-viewed video on the site, but it has since been removed.

Their singles "Alala" and "Off The Hook" have been featured in the video game Forza Motorsport 2. FIFA 08 also features "Off The Hook". Their song Jager Yoga, features in the soundtrack of FIFA 09.

In April 2008, Iracema Trevisan left the band; Adriano Cintra replaced her on bass guitar. The band is currently working with a session drummer , Jon Harper of The Cooper Temple Clause.

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Cascading Style Sheets

CSS.svg

Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation (that is, the look and formatting) of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can be applied to any kind of XML document, including SVG and XUL.

CSS is designed primarily to enable the separation of document content (written in HTML or a similar markup language) from document presentation, including elements such as the colors, fonts, and layout. This separation can improve content accessibility, provide more flexibility and control in the specification of presentation characteristics, enable multiple pages to share formatting, and reduce complexity and repetition in the structural content (such as by allowing for tableless web design). CSS can also allow the same markup page to be presented in different styles for different rendering methods, such as on-screen, in print, by voice (when read out by a speech-based browser or screen reader) and on Braille-based, tactile devices. While the author of a document typically links that document to a CSS stylesheet, readers can use a different stylesheet, perhaps one on their own computer, to override the one the author has specified.

CSS specifies a priority scheme to determine which style rules apply if more than one rule matches against a particular element. In this so-called cascade, priorities or weights are calculated and assigned to rules, so that the results are predictable.

The CSS specifications are maintained by the World Wide Web Consortium (W3C). Internet media type (MIME type) text/css is registered for use with CSS by RFC 2318 (March 1998).

CSS has a simple syntax, and uses a number of English keywords to specify the names of various style properties.

A style sheet consists of a list of rules. Each rule or rule-set consists of one or more selectors and a declaration block. A declaration-block consists of a list of semicolon-separated declarations in braces. Each declaration itself consists of a property, a colon (:), a value, then a semi-colon (;).

In CSS, selectors are used to declare which elements a style applies to, a kind of match expression. Selectors may apply to all elements of a specific type, or only those elements which match a certain attribute; elements may be matched depending on how they are placed relative to each other in the markup code, or on how they are nested within the document object model.

In addition to these, a set of pseudo-classes can be used to define further behavior. Probably the best-known of these is :hover, which applies a style only when the user 'points to' the visible element, usually by holding the mouse cursor over it. It is appended to a selector as in a:hover or #elementid:hover. Other pseudo-classes and pseudo-elements are, for example, :first-line, :visited or :before. A special pseudo-class is :lang(c), "c".

A pseudo-class selects entire elements, such as :link or :visited, whereas a pseudo-element makes a selection that may consist of partial elements, such as :first-line or :first-letter.

Selectors may be combined in other ways too, especially in CSS 2.1, to achieve greater specificity and flexibility.

Prior to CSS, nearly all of the presentational attributes of HTML documents were contained within the HTML markup; all font colors, background styles, element alignments, borders and sizes had to be explicitly described, often repeatedly, within the HTML. CSS allows authors to move much of that information to a separate stylesheet resulting in considerably simpler HTML markup.

Headings (h1 elements), sub-headings (h2), sub-sub-headings (h3), etc., are defined structurally using HTML. In print and on the screen, choice of font, size, color and emphasis for these elements is presentational.

Prior to CSS, document authors who wanted to assign such typographic characteristics to, say, all h2 headings had to use the HTML font and other presentational elements for each occurrence of that heading type. The additional presentational markup in the HTML made documents more complex, and generally more difficult to maintain. In CSS, presentation is separated from structure. In print, CSS can define color, font, text alignment, size, borders, spacing, layout and many other typographic characteristics. It can do so independently for on-screen and printed views. CSS also defines non-visual styles such as the speed and emphasis with which text is read out by aural text readers. The W3C now considers the advantages of CSS for defining all aspects of the presentation of HTML pages to be superior to other methods. It has therefore deprecated the use of all the original presentational HTML markup.

CSS information can be provided by various sources. CSS style information can be either attached as a separate document or embedded in the HTML document. Multiple style sheets can be imported. Different styles can be applied depending on the output device being used; for example, the screen version can be quite different from the printed version, so that authors can tailor the presentation appropriately for each medium.

One of the goals of CSS is also to allow users a greater degree of control over presentation; those who find the red italic headings difficult to read may apply other style sheets to the document. Depending on their browser and the web site, a user may choose from various stylesheets provided by the designers, may remove all added style and view the site using their browser's default styling or may perhaps override just the red italic heading style without altering other attributes.

Such a file is stored locally and is applicable if that has been specified in the browser options. "!important" means that it prevails over the author specifications.

Style sheets have existed in one form or another since the beginnings of SGML in the 1970s. Cascading Style Sheets were developed as a means for creating a consistent approach to providing style information for web documents.

As HTML grew, it came to encompass a wider variety of stylistic capabilities to meet the demands of web developers. This evolution gave the designer more control over site appearance but at the cost of HTML becoming more complex to write and maintain. Variations in web browser implementations made consistent site appearance difficult, and users had less control over how web content was displayed.

To improve the capabilities of web presentation, nine different style sheet languages were proposed to the W3C's www-style mailing list. Of the nine proposals, two were chosen as the foundation for what became CSS: Cascading HTML Style Sheets (CHSS) and Stream-based Style Sheet Proposal (SSP). First, Håkon Wium Lie (now the CTO of Opera Software) proposed Cascading HTML Style Sheets (CHSS) in October 1994, a language which has some resemblance to today's CSS. Bert Bos was working on a browser called Argo which used its own style sheet language, Stream-based Style Sheet Proposal (SSP). Lie and Bos worked together to develop the CSS standard (the 'H' was removed from the name because these style sheets could be applied to other markup languages besides HTML).

Unlike existing style languages like DSSSL and FOSI, CSS allowed a document's style to be influenced by multiple style sheets. One style sheet could inherit or "cascade" from another, permitting a mixture of stylistic preferences controlled equally by the site designer and user.

Håkon's proposal was presented at the "Mosaic and the Web" conference in Chicago, Illinois in 1994, and again with Bert Bos in 1995. Around this time, the World Wide Web Consortium was being established; the W3C took an interest in the development of CSS, and it organized a workshop toward that end chaired by Steven Pemberton. This resulted in W3C adding work on CSS to the deliverables of the HTML editorial review board (ERB). Håkon and Bert were the primary technical staff on this aspect of the project, with additional members, including Thomas Reardon of Microsoft, participating as well. By the end of 1996, CSS was ready to become official, and the CSS level 1 Recommendation was published in December.

Development of HTML, CSS, and the DOM had all been taking place in one group, the HTML Editorial Review Board (ERB). Early in 1997, the ERB was split into three working groups: HTML Working group, chaired by Dan Connolly of W3C; DOM Working group, chaired by Lauren Wood of SoftQuad; and CSS Working group, chaired by Chris Lilley of W3C.

The CSS Working Group began tackling issues that had not been addressed with CSS level 1, resulting in the creation of CSS level 2 on November 4, 1997. It was published as a W3C Recommendation on May 12, 1998. CSS level 3, which was started in 1998, is still under development as of 2009.

In 2005 the CSS Working Groups decided to enforce the requirements for standards more strictly. This meant that already published standards like CSS 2.1, CSS 3 Selectors and CSS 3 Text were pulled back from Candidate Recommendation to Working Draft level.

Although the CSS1 specification was completed in 1996 and Microsoft's Internet Explorer 3 was released in that year featuring some limited support for CSS, it would be more than three years before any web browser achieved near-full implementation of the specification. Internet Explorer 5.0 for the Macintosh, shipped in March 2000, was the first browser to have full (better than 99 percent) CSS1 support, surpassing Opera, which had been the leader since its introduction of CSS support 15 months earlier. Other browsers followed soon afterwards, and many of them additionally implemented parts of CSS2. As of July 2008, no (finished) browser has fully implemented CSS2, with implementation levels varying (see Comparison of layout engines (CSS)).

Even though early browsers such as Internet Explorer 3 and 4, and Netscape 4.x had support for CSS, it was typically incomplete and afflicted with serious bugs. This was a serious obstacle for the adoption of CSS.

When later 'version 5' browsers began to offer a fairly full implementation of CSS, they were still incorrect in certain areas and were fraught with inconsistencies, bugs and other quirks. The proliferation of such CSS-related inconsistencies and even the variation in feature support has made it difficult for designers to achieve a consistent appearance across platforms. Some authors commonly resort to using some workarounds such as CSS hacks and CSS filters in order to obtain consistent results across web browsers and platforms.

Problems with browsers' patchy adoption of CSS along with errata in the original specification led the W3C to revise the CSS2 standard into CSS2.1, which may be regarded as something nearer to a working snapshot of current CSS support in HTML browsers. Some CSS2 properties which no browser had successfully implemented were dropped, and in a few cases, defined behaviours were changed to bring the standard into line with the predominant existing implementations. CSS2.1 became a Candidate Recommendation on February 25, 2004, but CSS2.1 was pulled back to Working Draft status on June 13, 2005, and only returned to Candidate Recommendation status on July 19, 2007.

To achieve maximum efficiency in making CSS cross-browser compatible, a large number of web developers use a CSS Reference Manual. This is a document, often organized alphabetically, designed as a quick reference for web developers when working with CSS based webpages.

In the past, some web servers were configured to serve all documents with the filename extension .css as mime type application/x-pointplus rather than text/css. At the time, the Net-Scene company was selling PointPlus Maker to convert PowerPoint files into Compact Slide Show files (using a .css extension).

CSS has various levels and profiles. Each level of CSS builds upon the last, typically adding new features and typically denoted as CSS1, CSS2, and CSS3. Profiles are typically a subset of one or more levels of CSS built for a particular device or user interface. Currently there are profiles for mobile devices, printers, and television sets. Profiles should not be confused with media types which were added in CSS2.

The W3C maintains the CSS1 Recommendation.

CSS level 2 was developed by the W3C and published as a Recommendation in May 1998. A superset of CSS1, CSS2 includes a number of new capabilities like absolute, relative, and fixed positioning of elements, the concept of media types, support for aural style sheets and bidirectional text, and new font properties such as shadows. The W3C maintains the CSS2 Recommendation.

CSS level 2 revision 1 or CSS 2.1 fixes errors in CSS2, removes poorly-supported features and adds already-implemented browser extensions to the specification. While it was a Candidate Recommendation for several months, on June 15, 2005 it was reverted to a working draft for further review. It was returned to Candidate Recommendation status on 19 July 2007.

CSS level 3 is currently under development. The W3C maintains a CSS3 progress report. CSS3 is modularized and will consist of several separate Recommendations. The W3C CSS3 Roadmap provides a summary and introduction.

A CSS filter is a coding technique that aims to effectively hide or show parts of the CSS to different browsers, either by exploiting CSS-handling quirks or bugs in the browser, or by taking advantage of lack of support for parts of the CSS specifications. Using CSS filters, some designers have gone as far as delivering entirely different CSS to certain browsers in order to ensure that designs are rendered as expected. Because very early web browsers were either completely incapable of handling CSS, or render CSS very poorly, designers today often routinely use CSS filters that completely prevent these browsers from accessing any of the CSS. Internet Explorer support for CSS began with IE 3.0 and increased progressively with each version. By 2008, the first Beta of Internet Explorer 8 offered support for CSS 2.1 in its best web standards mode.

An example of a well-known CSS browser bug is the Internet Explorer box model bug, where box widths are interpreted incorrectly in several versions of the browser, resulting in blocks which are too narrow when viewed in Internet Explorer, but correct in standards-compliant browsers. The bug can be avoided in Internet Explorer 6 by using the correct doctype in (X)HTML documents. CSS hacks and CSS filters are used to compensate for bugs such as this, just one of hundreds of CSS bugs that have been documented in various versions of Netscape, Mozilla Firefox, Opera, and Internet Explorer (including Internet Explorer 7).

Even when the availability of CSS-capable browsers made CSS a viable technology, the adoption of CSS was still held back by designers' struggles with browsers' incorrect CSS implementation and patchy CSS support. Even today, these problems continue to make the business of CSS design more complex and costly than it should be, and cross-browser testing remains a necessity. Other reasons for continuing non-adoption of CSS are: its perceived complexity, authors' lack of familiarity with CSS syntax and required techniques, poor support from authoring tools, the risks posed by inconsistency between browsers and the increased costs of testing.

Currently there is strong competition between Mozilla's Gecko layout engine, the WebKit layout engine used in Apple's Safari, the similar KHTML engine used in KDE's Konqueror browser, and Opera's Presto layout engine - each of them is leading in different aspects of CSS. As of April 2009, Internet Explorer 8 has the most complete implementation of CSS 2.1 according to the Webdevout Web Browsers Standards Support Summary, scoring 99%.

By combining CSS with the functionality of a Content Management System, a considerable amount of flexibility can be programmed into content submission forms. This allows a contributor, who may not be familiar or able to understand or edit CSS or HTML code to select the layout of an article or other page they are submitting on-the-fly, in the same form. For instance, a contributor, editor or author of an article or page might be able to select the number of columns and whether or not the page or article will carry an image. This information is then passed to the Content Management System, and the program logic will evaluate the information and determine, based on a certain number of combinations, how to apply classes and IDs to the HTML elements, therefore styling and positioning them according to the pre-defined CSS for that particular layout type. When working with large-scale, complex sites, with many contributors such as news and informational sites, this advantage weighs heavily on the feasibility and maintenance of the project.

When CSS is used effectively, in terms of inheritance and "cascading," a global stylesheet can be used to affect and style elements site-wide. If the situation arises that the styling of the elements should need to be changed or adjusted, these changes can be made easily, simply by editing a few rules in the global stylesheet. Before CSS, this sort of maintenance was more difficult, expensive and time-consuming.

A stylesheet will usually be stored in the browser cache, and can therefore be used on multiple pages without being reloaded, increasing download speeds and reducing data transfer over a network.

With a simple change of one line, a different stylesheet can be used for the same page. This has advantages for accessibility, as well as providing the ability to tailor a page or site to different target devices. Furthermore, devices not able to understand the styling will still display the content.

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Central Security Service

CSS seal

The Central Security Service (CSS) is an agency of the U.S. Department of Defense, established in 1972 by a Presidential Directive to promote full partnership between the National Security Agency (NSA) and the Service Cryptologic Elements (SCE) of the United States Armed Forces.

The blue background of the CSS emblem represents "fidelity" and "steadfastness", with the symbols for the cryptologic service elements provided shown clockwise from top right as follows: Army Intelligence and Security Command, United States Marine Corps, Naval Security Group, United States Coast Guard and Air Force Intelligence, Surveillance and Reconnaissance Agency with the symbol of the National Security Agency in the center.

According to James Bamford, NSA/CSS was initially conceived as a separate "fourth service" beside the three U.S. armed services. The latter three resisted this idea, and therefore the CSS was founded as an inter-service organization. The day-to-day work of the CSS is to capture enemy signals (radar, telemetry, radio/satellite communications) using the means of the involved service. For example, the Navy has special submarines for tapping undersea cables; the Air Force operates aircraft with sophisticated antennas and processing gear to listen to enemy radar and radio; and on the ground, the Army operates similar eavesdropping equipment.

The Naval Security Group is a significant addition of SIGINT and COMSEC expertise to the organization. Managing the logistics of collection across the globe and securing the systems used inside the agency and other branches of the military are particularly useful contributions from the Naval Security Group. The Computer Network Defense Red Team run by the Navy at the Fleet Information Warfare Center also operates directly under the Naval Security Group and provides critical operational and exercise support to commands to improve their ability to fend off malicious computer activity. Red Team refers to a group of subject-matter experts tasked with playing the role of the enemy in training exercises, often referred to as peer review or penetration testing in private industry.

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Chirp spread spectrum

A linear frequency modulated upchirp in the time domain

Chirp spread spectrum (CSS) is a spread spectrum technique that uses wideband linear frequency modulated chirp pulses to encode information. A chirp is a sinusoidal signal whose frequency increases or decreases over a certain amount of time. Below is an example of an upchirp - as you can see, the frequency increases linearly over time.

As with other spread spectrum methods, Chirp Spread Spectrum uses its entire allocated bandwidth to broadcast a signal, making it robust to channel noise. Further, because the chirps utilize a broad band of the spectrum, Chirp Spread Spectrum is also resistant to multi-path fading even when operating at very low power. However, it is unlike direct-sequence spread spectrum (DSSS) or frequency-hopping spread spectrum (FHSS) in that it does not add any pseudo-random elements to the signal to help distinguish it from noise on the channel, instead relying on the linear nature of the chirp pulse. Additionally, Chirp Spread Spectrum is resistant to the Doppler effect, which is typical in mobile radio applications.

Chirp Spread Spectrum was originally designed to compete with ultra-wideband for precision ranging and low-rate wireless networks in the 2.45 GHz band. However, since the release of IEEE 802.15.4a (also known as IEEE 802.15.4a-2007), it is no longer actively being considered by the IEEE for standardization in the area of precision ranging. Currently, Nanotron Technologies, which produces real-time location devices and was the primary force behind getting CSS added to IEEE 802.15.4a, is the only seller of wireless devices using CSS. In particular, their primary product, the nanoLOC TRX transceiver, uses CSS and is marketed as a network device with real-time location and RFID abilities. Some areas where this type of technology can be useful are medical applications, logistics (i.e. containers need to be tracked), and government/security applications. Nanotron even tested the TRX Transceiver for industrial monitoring and control in a steel mill and it survived when the computer and display that were interfacing with it failed because of the heat.

Chirp Spread Spectrum is ideal for applications requiring low power usage and needing relatively low amounts of bandwidth (1 Mbit/s or less). In particular, IEEE 802.15.4a specifies CSS as a technique for use in Low-Rate Wireless Personal Area Networks (LR-WPAN). However, whereas IEEE 802.15.4-2006 standard specifies that WPANs encompass an area of 10 m or less, IEEE 802.15.4a-2007, specifies CSS as a physical layer to be used when longer ranges and devices moving at high speeds are part of your network. Nanotron's CSS implementation was actually seen to work at a range of 570 meters between devices. Further, Nanotron's implementation can work at data rates of up to 2 Mbit/s - higher than specified in 802.15.4a. Finally, the IEEE 802.15.4a PHY standard actually mixes CSS encoding techniques with Differential Phase Shift Keying Modulation (DPSK) to achieve better data rates.

Chirp Spread Spectrum may also be used in the future for military applications as it is very difficult to detect and intercept when operating at low power.

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Cross-site scripting

Bugzilla bug in the U.S. National Vulnerability Database

Cross-site scripting (XSS) is a type of computer security vulnerability typically found in web applications which allow code injection by malicious web users into the web pages viewed by other users. Examples of such code include HTML code and client-side scripts. An exploited cross-site scripting vulnerability can be used by attackers to bypass access controls such as the same origin policy. Vulnerabilities of this kind have been exploited to craft powerful phishing attacks and browser exploits. As of 2007, cross-site scripting carried out on websites were roughly 80% of all documented security vulnerabilities. Often during an attack "everything looks fine" to the end-user who may be subject to unauthorized access, theft of sensitive data, and financial loss.

The term "cross-site scripting" originated from the fact that a malicious web site could load another web site into another frame or window, then use Javascript to read/write data on the other web site. Over time the definition changed to mean the injection of HTML/Javascript into a web page, which may be confusing because the name is no longer an accurate description of the current definition.

In recent years XSS surpassed buffer overflows to become the most common of all publicly reported security vulnerabilities. Likely at least 68% of websites are open to XSS attacks on their users. In general, cross-site scripting holes can be seen as vulnerabilities present in web pages which allow attackers to bypass security mechanisms. By finding clever ways of injecting malicious scripts into web pages, an attacker can gain elevated access privileges to sensitive page content, session cookies, and a variety of other objects. Cross-site scripting was originally referred to as CSS, although this usage has been largely discontinued due to confusion with the same abbreviation for Cascading Style Sheets.

XSS attacks are written in a client-side scripting language, most often a dialect of ECMAScript (e.g. JavaScript, JScript), sometimes including some markup language such as HTML or XHTML as well. XSS sometimes reaches other technologies including Sun Microsystems's Java, Microsoft's ActiveX and VBScript, Adobe's Flash and ActionScript, and RSS and Atom feeds.

XSS vulnerabilities have been reported and in some cases exploited since the 1990s. Some of the prominent sites affected were the search engine Google, the email services of Google and Yahoo!, the social networking sites Facebook, MySpace and Orkut. The developers of MediaWiki have fixed at least 20 XSS holes in order to protect Wikipedia and other wiki users.

Browser vendors began in 2008 to stop their users from accessing blacklisted web resources. Opera as of version 9.5 blocks on a page-by-page basis based on Haute Secure, Netcraft, and PhishTank data. At the time of Opera's release, both Microsoft's Internet Explorer (IE) and Mozilla Firefox public betas had related features. Firefox blocks are site-by-site and based on Google and StopBadware.org data.

Three distinct types of XSS vulnerabilities exist: non-persistent, persistent and DOM-based (which can be either persistent or non-persistent).

The DOM-based or Type 0 XSS vulnerability, also referred to as local cross-site scripting, is based on the standard object model for representing HTML or XML called the Document Object Model or DOM for short. With DOM-based cross-site scripting vulnerabilities, the problem exists within a page's client-side script itself. For instance, if a piece of JavaScript accesses a URL request parameter and uses this information to write some HTML to its own page, and this information is not encoded using HTML entities, an XSS hole will likely be present, since this written data will be re-interpreted by browsers as HTML which could include additional client-side script.

In practice, exploiting such a hole would be very similar to the exploit of non-persistent type vulnerabilities (see below), except in one very important situation. Because of the way older versions of Microsoft Internet Explorer treat client-side script in objects located in the "local zone" (for instance, on the client's local hard drive), an XSS hole of this kind in a local page can result in remote execution vulnerabilities. For example, if an attacker hosts a malicious website, which contains a link to a vulnerable page on a client's local system, a script could be injected and would run with privileges of that user's browser on their system. (Local HTML pages are commonly installed with standard software packages, including Internet Explorer.) This bypasses the entire client-side sandbox, not just the cross-domain restrictions that are normally bypassed with XSS exploits. The Local Machine Zone Lockdown in IE6 on Windows XP Service Pack 2 was implemented to prevent attackers from executing scripts in the local file zone but did not protect Internet Explorer users from similar vulnerabilities.

The non-persistent or Type 1 cross-site scripting hole is also referred to as a reflected vulnerability, and is by far the most common type. These holes show up when data provided by a web client is used immediately by server-side scripts to generate a page of results for that user. If unvalidated user-supplied data is included in the resulting page without HTML encoding, this will allow client-side code to be injected into the dynamic page. A classic example of this is in site search engines: if one searches for a string which includes some HTML special characters, often the search string will be redisplayed on the result page to indicate what was searched for, or will at least include the search terms in the text box for easier editing. If any occurrence of the search terms is not HTML entity encoded, an XSS hole will result.

At first blush, this does not appear to be a serious problem since users can only inject code into their own pages. However, with a small amount of social engineering, an attacker could convince a user to follow a malicious URL which injects code into the results page, giving the attacker full access to that page's content. Due to the general requirement of the use of some social engineering in this case (and normally in Type 0 vulnerabilities as well), many programmers have disregarded these holes as not terribly important. This misconception is sometimes applied to XSS holes in general (even though this is only one type of XSS) and there is often disagreement in the security community as to the importance of cross-site scripting vulnerabilities.

The persistent or Type 2 XSS vulnerability is also referred to as a stored or second-order vulnerability, and it allows the most powerful kinds of attacks. A type 2 XSS vulnerability exists when data provided to a web application by a user is first stored persistently on the server (in a database, filesystem, or other location), and later displayed to users in a web page without being encoded using HTML entities. A classic example of this is with online message boards, where users are allowed to post HTML formatted messages for other users to read.

Persistent XSS can be more significant than other types because an attacker's malicious script is rendered more than once. Potentially, such an attack could affect a large number of users with little need for social engineering, and the application could be infected by a cross-site scripting virus or worm.

The methods of injection can vary a great deal, and an attacker may not need to use the web application itself to exploit such a hole. Any data received by the web application (via email, system logs, etc) that can be controlled by an attacker must be encoded prior to re-display in a dynamic page, else an XSS vulnerability of this type could result.

Attackers intending to exploit cross-site scripting vulnerabilities must approach each class of vulnerability differently. For each class, a specific attack vector is described here. The names below are technical terms, taken from the cast of characters commonly used in computer security.

Please note, the preceding examples are merely a representation of common methods of exploit and are not meant to encompass all vectors of attack.

Avoiding XSS requires action on the part of the user. Defense against XSS falls also to content and web application developers, and to browser vendors. Users can usually disable scripting, several best practices exist for content developers, web applications can be tested and reviewed before release, and some browsers today implement a few access-control policies.

Several high profile security vulnerabilities followed the Netscape introduction in 1995 of the JavaScript language. Netscape began to realize some of the security risks of allowing a Web server to send executable code to a browser (even if only in a browser sandbox). The company introduced the same origin policy in Netscape Navigator version 2. One key problem is the case where users have more than one browser window or tab open at once. In some instances, a script from one page should be allowed to access data from another page or object, but in others, this should be strictly forbidden because a malicious website could attempt to steal sensitive information. The policy forbids browsers to load a script when it crosses the boundary of the current Window object unless the script originated from the same domain and over the same protocol and the same port if port is specified. Essentially, this policy was intended to allow interaction between objects and pages but in theory a malicious Web site would not be able to access sensitive data in another browser window. Unfortunately browser vendors implemented the policy in different ways and the result was unpredictable behavior. The policy also had loopholes, for example, an HTML element embedded in a page or resource at the origin host may link to a script hosted elsewhere and the browser will load that script when it loads the page. Since then, other similar access-control policies have been adopted in other browsers and client-side scripting languages to protect end-users from malicious Web sites but the policies may depend on the user themself to guide access control according to their preferences. For example, digital signatures might identify scripts and their source to the user or user agent before a script can load.

One way to eliminate some XSS vulnerabilities is to escape (either locally or at the server) all untrusted data based on where that data is to be placed in the HTML document. This escaping prevents the data from being interpreted and executed.There are several different escaping schemes that must be used, including HTML numeric entity encoding, JavaScript escaping, CSS escaping, and URL (or percent) encoding. Most web applications that do not need to accept rich data can use escaping to completely eliminate the risk of XSS. However, although it is widely recommended, simply performing HTML entity encoding on the five XML significant characters is not sufficient to prevent many forms of XSS. Encoding can be tricky, and the use of a security encoding library is highly recommended.

Unfortunately, users of many kinds of web applications (commonly forums and webmail) wish to allow users to utilize some of the features HTML provides, such as bold tags for instance. Some web applications such as social networking sites like MySpace and mainstream forum and blog software like WordPress and Movable Type attempt to identify malicious HTML constructs, and neutralize them, either by removing or encoding them. But due to the flexibility and complexity of HTML and related standards, and the continuous addition of new features, it is almost impossible to know for sure if all possible injections are eliminated. Capabilities differ greatly among filtering systems and as of 2007 in Google's case were being written in house. In order to eliminate certain injections, any server-side algorithm must either reject broken HTML, understand how every browser will interpret broken HTML, or (preferably) fix the HTML to be well-formed using techniques akin to those of HTML Tidy.

Input validation for all potentially malicious data sources is another way to mitigate XSS. This is a common theme in application development (even outside of web development) and is generally very useful. For instance, if a form accepts some field, which is supposed to contain a phone number, a server-side routine could remove all characters other than digits, parentheses, and dashes, such that the result cannot contain a script. Input validation may help to mitigate other injection attacks such as SQL injection as well. While effective for most types of input, there are times when an application, by design, must be able to accept special HTML characters, such as '<' and '>'. In these situations, HTML entity encoding is the only option.

Besides content filtering, other methods for XSS mitigation are also commonly used. One example is that of cookie security. Many web applications rely on session cookies for authentication between individual HTTP requests, and because client-side scripts generally have access to these cookies, simple XSS exploits can steal these cookies. To mitigate this particular threat (though not the XSS problem in general), many web applications tie session cookies to the IP address of the user who originally logged in, and only permit that IP to use that cookie. This is effective in most situations (if an attacker is only after the cookie), but obviously breaks down in situations where an attacker is behind the same NATed IP address or web proxy. IE (since version 6) and Firefox (since version 2.0.0.5) have an HttpOnly flag which allows a web server to set a cookie that is unavailable to client-side scripts but while beneficial, the feature does not prevent cookie theft nor can it prevent attacks within the browser.

Finally, while Web 2.0 and Ajax designers favor the use of JavaScript, some web applications are written to (sometimes optionally) operate completely without the need for client-side scripts. This allows users, if they choose, to disable scripting in their browsers before using the application. In this way, even potentially malicious client-side scripts could be inserted unescaped on a page, and users would not be susceptible to XSS attacks.

Many browsers can be configured to disable client-side scripts on a per-domain basis. If scripting is allowed by default, then this approach is of limited value, since it blocks bad sites only after the user knows that they are bad, which is too late. Functionality that blocks all scripting and external inclusions by default and then allows the user to enable it on a per-domain basis is more effective. This has been possible for a long time in IE (since version 4) by setting up its so called "Security Zones", and in Opera (since version 9) using its "Site Specific Preferences". A solution for Firefox and other Gecko-based browsers is the open source NoScript add-on which has anti-XSS protection.

The most significant problem with blocking all scripts on all websites by default is substantial reduction in functionality and responsiveness (client-side scripting can be much faster than server-side scripting because it does not need to connect to a remote server and the page or frame does not need to be reloaded). Another problem with script blocking is that many users do not understand it, and do not know how to properly secure their browsers. Another drawback is that many sites do not work without client-side scripting, forcing users to disable protection for that site and opening their systems to the threat. The Firefox NoScript extension enables users to allow scripts selectively from a given page while disallowing others on the same page. For example, scripts from example.com could be allowed, while scripts from advertisingagency.com that are attempting to run on the same page could be disallowed.

Several classes of vulnerabilities or attack techniques are related to XSS. Cross-zone scripting exploits "zone" concepts in software and usually executes code with a greater privilege. HTTP header injection can be used to create cross-site scripting conditions in addition to allowing attacks such as HTTP response splitting. Cross-site request forgery (CSRF/XSRF) is almost the opposite of XSS, in that rather than exploiting the user's trust in a site, the attacker exploits the site's trust in the client software, submitting requests that the site believes come from its own authenticated users. SQL injection exploits a vulnerability in the database layer of an application. When user input is incorrectly filtered any SQL statements can be executed by the application. Content spoofing is a similar attack where markup language is injected without script with the intention of presenting unintended content as native to the site instead of running malicious code in a victim's browser.

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Confederate States Navy

CSS Alabama, a ship of the Confederate States Navy

The Confederate States Navy (CSN) was the naval branch of the Confederate States armed forces established by an act of the Confederate Congress on February 21, 1861. It was responsible for Confederate naval operations during the American Civil War. The two major tasks of the Confederate Navy during the whole of its existence were the protection of Southern harbors and coastlines from outside invasion, and making the war costly for the North by attacking merchant ships and breaking the Union Blockade.

The C.S. Navy could never achieve equality with the Union Navy, and used technological innovation, such as ironclads, submarines, torpedo boats, and naval mines (then known as torpedoes) to gain advantage over the Union Navy. In February 1861, the Confederate Navy had thirty ships, only fourteen of which were seaworthy, while the Union Navy had ninety vessels. The C.S. Navy eventually grew to 101 ships to meet the rise in naval conflicts and enemy threats.

On April 20, 1861, the Union abandoned the Norfolk Navy Yard but did not burn the facility or ships. (The South's other major navy yard was in Pensacola, Florida). Ships left in the Norfolk shipyard included a screw frigate named USS Merrimack. It was C.S. Navy Secretary Stephen Mallory's idea to armor the upper sides of the Merrimack with iron plate, making it "iron clad". The ship was renamed CSS Virginia and later fought the USS Monitor to a draw in the Battle of Hampton Roads.

The act of the Confederate Congress that created the Confederate Navy on February 21, 1861 also appointed Stephen Mallory as Secretary of the Department of the Navy. Mallory was experienced as an admiralty lawyer in his home state of Florida, and he had served for a time as the chairman of the Naval Affairs Committee while he was a United States senator.

In addition to the ships included in the report of the committee, the Navy also had one ironclad floating battery, presented to the Confederate States by the state of Georgia, one ironclad ram donated by the state of Alabama, and numerous privateers making war on Union merchant ships.

President Davis was not confident of his executive authority to issue letters of marque and called a special session of Congress on April 29 to formally authorize the hiring of privateers in the name of the Confederate States. On May 6, the Confederate Congress passed "An act recognizing the existence of war between the United States and the Confederate States, and concerning letters of marque, prizes, and prize goods." Then, on May 14, 1861, "An act regulating the sale of prizes and the distribution thereof," was also passed. Both acts granted the president power to issue letters of marque and detailed regulations as to the conditions on which letters of marque should be granted to private vessels, the conduct and behavior of the officers and crews of such vessels, and the disposal of such prizes made by privateer crews. The manner in which Confederate privateers operated was generally similar to those of privateers of the United States or of European nations.

The 1856, Declaration of Paris outlawed privateering for such nations as Great Britain and France, but the United States had neither signed nor endorsed the declaration. Therefore, privateering was constitutionally legal in both the United and Confederate States, as well as Portugal, Russia, the Ottoman Empire, and Germany. However, the United States did not acknowledge the Confederate States as a nation and denied the legitimacy of any letters of marque issued by its government. Union President Abraham Lincoln declared all medicines to the South to be contraband, and that any captured Confederate privateers were to be hanged as pirates. Ultimately, no one was hanged for privateering because the Confederate government threatened to retaliate against prisoners of war.

Initially, Confederate privateers operated primarily from New Orleans, but activity was soon concentrated in the Atlantic as the Union Navy began expanding its operations. Throughout the war, Confederate privateers successfully harassed Union merchant ships, sank several warships, and harmed the Northern economy.

One of the more well-known ships was CSS Virginia (formerly known as "USS Merrimack"), a Union ironclad(1855). In 1862 she fought USS Monitor in the Battle of Hampton Roads, an event that came to symbolize the end of the dominance of large wooden sailing warships.

Confederate raiders were also used to disrupt Union merchant shipping, the most famous of them being the CSS Alabama, a ship made in Britain.

The CSS Shenandoah fired the last shot of the American Civil War in late June 1865, and finally surrendered in early November 1865.

There was a Revolutionary War-era frigate known as USS Confederacy, unrelated to the CSN. There was however a CSS United States, the name of the USS United States in 1861–1862, when she was captured and used by the CSN.

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Catalina Sky Survey

Catalina Sky Survey is a project to discover comets and asteroids, and to search for Near-Earth objects. More specifically, to search for potentially hazardous asteroids (PHAs), that may pose a threat of impact.

Technology has now advanced to a level where humans are capable to inventory the NEO population. Given the catastrophic consequences of a collision with a large object, the NEO Observations Program (NEOO) is a result of a 1998 congressional directive to NASA to begin a program to identify 1 kilometer or larger objects to around 90 percent confidence level or better.

In addition to surveying how many NEOs there are, there are other benefits to this project. For example, humans can improve the known population distribution in the main belt, find the cometary distribution at larger perihelion distances, determining the distribution of NEOs as a product of collisional history and transport to the inner solar system, and identifying potential targets for flight projects.

The Catalina Sky Survey (CSS) and its affiliated Siding Spring Survey (SSS) are carrying out searches for NEOs, contributing to the Congressionally mandated goal.

CSS utilizes three telescopes, a 1.5 meter (60 inch) f/ 2 telescope on the peak of Mt. Lemmon, a 68 cm (27 inch) f/ 1.9 Schmidt telescope near Mt. Bigelow and a 0.5 meter (20 inch) Uppsala Schimidt telescope at Siding Spring Observatory in Australia. All three sites use identical, thermo-electrically cooled cameras and common software that was written by the CSS team. The cameras are cooled to approximately -100C so their dark current is about 1 electron per hour. These 4096x4096 pixel cameras provide a field of view (FOV) of 1 degree square on with the 1.5-m telescope and nearly 9 square degrees with the Catalina Schmidt. Nominal exposures are 30 seconds and the 1.5-m can reach objects fainter than 21.5V in that time.

CSS typically operates every clear night with the exception of a few nights centered on the full moon.

In 2005, CSS became the most prolific NEO survey surpassing Lincoln Near-Earth Asteroid Research (LINEAR) in total number of NEOs and PHAs discovered each year since. CSS discovered 310 NEOs in 2005, 396 in 2006, 466 in 2007, and in 2008 564 NEOs were found.

The CSS team is headed by Steve Larson of the Lunar and Planetary Laboratory of the University of Arizona.

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Source : Wikipedia