[Work In Progress]

About

Google Chrome is a freeware web browser developed by Google that uses the WebKit layout engine. It was first released as a beta version for Microsoft Windows on September 2, 2008, and the public stable release was on December 11, 2008. As of June 2012, Google Chrome has 32.76% worldwide usage share of web browsers, making it the most widely used web browser, according to StatCounter. In September 2008, Google released a large portion of Chrome's source code as an open source project called Chromium which Chrome releases continue to be based on.

History

For six years, Google's Chief Executive Eric Schmidt opposed the development of an independent web browser. He stated that "at the time, Google was a small company", and he did not want to go through "bruising browser wars". However, after co-founders Sergey Brin and Larry Page hired several Mozilla Firefox developers and built a demonstration of Chrome, Schmidt admitted that "It was so good that it essentially forced me to change my mind".

Announcement

The release announcement was originally scheduled for September 3, 2008, and a comic by Scott McCloud was to be sent to journalists and bloggers explaining the features within the new browser. Copies intended for Europe were shipped early and German blogger Philipp Lenssen of Google Blogoscoped made a scanned copy of the 38-page comic available on his website after receiving it on September 1, 2008. Google subsequently made the comic available on Google Books and mentioned it on their official blog along with an explanation for the early release.

Public release

The browser was first publicly released for Microsoft Windows (XP and later versions) on September 2, 2008 in 43 languages, officially a beta version. Chrome quickly gained about 1% usage share. After the initial surge, usage share dropped until it hit a low of 0.69% in October 2008. It then started rising again and by December 2008, Chrome again passed the 1% threshold.

In early January 2009, CNET reported that Google planned to release versions of Chrome for Mac OS X and Linux in the first half of the year.The first official Chrome OS X and Linux developer previews were announced on June 4, 2009 with a blog post^[17] saying they were missing many features and were intended for early feedback rather than general use.

In December 2009, Google released beta versions of Chrome for Mac OS X and Linux. Google Chrome 5.0, announced on May 25, 2010, was the first stable release to support all three platforms.

Chrome was one of the twelve browsers offered to European Economic Area users of Microsoft Windows in 2010.

Development

Chrome was assembled from 25 different code libraries from Google and third parties such as Mozilla's Netscape Portable Runtime, Network Security Services, NPAPI, as well as SQLite and a number of other open-source projects. The V8 JavaScript virtual machine was considered a sufficiently important project to be split off (as was Adobe/Mozilla's Tamarin) and handled by a separate team in Denmark coordinated by Lars Bak at Aarhus. According to Google, existing implementations were designed "for small programs, where the performance and interactivity of the system weren't that important", but web applications such as Gmail "are using the web browser to the fullest when it comes to DOM manipulations and JavaScript", and therefore would significantly benefit from a JavaScript engine that could work faster.

Chrome uses the WebKit rendering engine to display web pages, on advice from the Android team. Chrome is tested internally with unit testing, "automated user interface testing of scripted user actions", fuzz testing, as well as WebKit's layout tests (99% of which Chrome is claimed to have passed) and against commonly accessed websites inside the Google index within 20–30 minutes.

Google created Gears for Chrome, which added features for web developers typically relating to the building of web applications, including offline support. However, Google phased out Gears in favor of HTML5.

On January 11, 2011 the Chrome product manager, Mike Jazayeri, announced that Chrome will no longer support H.264 video codec for its HTML5 player, citing the desire to bring Google Chrome more in line with the currently available open codecs available in the Chromium project, which Chrome is based on. As of January 2012, there has been no announcement yet of which future version of Chrome will actually implement the removal of H.264 support.

On February 7, 2012, Google launched Google Chrome Beta for Android 4.0 (Ice Cream Sandwich) devices. In March 2012 Google announced it was working on a version of Chrome for both the Metro and desktop versions of Windows 8.

Enterprise deployment

In December 2010 Google announced that to make deploying Chrome easier in a business environment they would provide an official Chrome MSI package. For enterprise deployments it's important to have full-fledged MSI packages that can be customized via transform files, but the provided MSI[clarification needed] is only a very limiting MSI wrapper around the normal installer that does not fulfill all enterprise needs. The normal downloaded Chrome installer puts the browser in the user's local app data directory and provides invisible background updates, but the MSI package will allow installation at the system level, providing system administrators control over the update process-- it was formerly possible only when Chrome was installed using Google Pack. Google also created Group Policies to fine tune the behavior of Chrome in the business environment, for example setting automatic updates interval, disable auto-updates, a home page and to workaround their basic Windows design flaws and bugs if it comes to roaming profiles support, etc. Until version 18 the software is known not to be ready for enterprise deployments with roaming profiles.

Chromium

Chromium is the open source web browser project from which Google Chrome draws its source code.
The Chromium Project takes its name from the element chromium, the metal from which chrome is made. Google's intention, as expressed in the developer documentation, was that Chromium would be the name of the open source project and that the final product name would be Chrome. However, other developers have taken the Chromium code and released versions under the Chromium name and these are listed at community builds.

One of the major aims of the project is for Chrome to be a tabbed window manager, or shell for the web, as opposed to it being a traditional browser application. The application is designed specifically to have a minimalist user interface. The developers state that it "should feel lightweight (cognitively and physically) and fast".

There are several differences between Chromium and Google Chrome.

Chromium is the name given to the open source project and the browser source code released and maintained by the Chromium Project. It is possible to download the source code and build it manually on many platforms. Google takes this source code and adds:
Integrated Flash Player
Built-in PDF viewer
Built-in print preview and print system
The Google name and a different logo
An auto-update system called GoogleUpdate
An opt-in option for users to send Google their usage statistics and crash reports

RLZ tracking when Chrome is downloaded as part of marketing promotions and distribution partnerships. This transmits information in encoded form to Google, e.g., when and from where Chrome has been downloaded. In June 2010, Google confirmed that the RLZ tracking token is not present in versions of Chrome downloaded from the Google website directly or in any version of Chromium. The RLZ source code was also made open source at the same time so that developers can confirm what it is and how it works.

By default, Chromium only supports Vorbis, Theora and WebM codecs for the HTML5 audio and video tags; whereas Google Chrome supports these, plus AAC and MP3. On 11 January 2011, the Chrome Product manager, Mike Jazayeri, announced that Chrome will no longer support the H.264 video format for its HTML5 player, equally as Chromium does not. As of June 2012, however, Chrome still supports H.264. Certain Linux distributions may add support for other codecs to their customized versions of Chromium.

Features

Google Chrome aims to be secure, fast, simple and stable. There are extensive differences from its peers in Chrome's minimalistic user interface, which is atypical of modern web browsers. For example, Chrome does not render RSS feeds. One of Chrome's strengths is its application performance and JavaScript processing speed, both of which were independently verified by multiple websites to be the swiftest among the major browsers of its time. Many of Chrome's unique features had been previously announced by other browser developers, but Google was the first to implement and publicly release them. For example, its most prominent graphical user interface (GUI) innovation, the merging of the address bar and search bar (the Omnibox), was first announced by Mozilla in May 2008 as a planned feature for Firefox.

Web standards support

The first release of Google Chrome passed both the Acid1 and Acid2 tests. Beginning with version 4.0, Chrome has passed all aspects of the Acid3 test.

Chrome has currently quite good support for JavaScript/ECMAScript according to Ecma International's ECMAScript standards conformance Test 262(version ES5.1 of 2012-05-18). This test reports as final score the number of tests a browser failed; hence lower scores are better. In this test, Chrome version 20.0.1132.21 scored 17/11570, the beta version 21.0.1180 scored 17/11570, and the dev version 22.0.1215.1 scored 16/11570. For comparison, Internet Explorer 9 has a score of 600+.

On the official CSS 2.1 test suite by standardization organization W3C, WebKit, the Chrome rendering engine, passes 89.75% (89.38% out of 99.59%) of covered CSS 2.1 tests.

On the HTML5 test (April, 2012 – version 3.0), Chrome version 19.0.1084.52 scored 402 out of 500, with 13 bonus points. The beta version 20.0.1132.34 scored 414 out of 500, with 13 bonus points. The dev version 21.0.1163.0 scored 442 out of 500, with 13 bonus points.