Safari (web browser)

Safari is a web browser developed by Apple Inc. First released as a public beta on 7 January 2003 on the company's Mac OS X operating system, it became Apple's default browser beginning with Mac OS X v10.3 "Panther". Apple has also made Safari the native browser for the iPhone OS. A version of Safari for the Microsoft Windows operating system first released on June 11, 2007 supports Windows XP, Windows Vista, and Windows 7.The current stable release of the browser is 4.0.3 for Mac OS X and Windows. Safari had a 4.24% market share in September 2009.



History and development

Until 1997, Apple Macintosh computers had shipped with Netscape Navigator and Cyberdog only. Internet Explorer for Mac was subsequently included with Mac OS 8.1 onwards as the default web browser, as part of the five year agreement between Apple and Microsoft. However, Netscape Navigator continued to be included. Microsoft released three major versions of Internet Explorer for Mac that were bundled with Mac OS 8 and Mac OS 9. Microsoft subsequently released a Mac OS X edition of Internet Explorer 5, which was included as the default browser in all Mac OS X releases from Mac OS X DP4 until Mac OS X v10.2.

On January 7, 2003, Steve Jobs announced that Apple had developed their own web browser based on KHTML rendering engine, called Safari. They released the first beta version that day and a number of official and unofficial beta versions followed, until version 1.0 was released on June 23, 2003. Available as a separate download initially, it was included with the Mac OS X v10.3 release on October 24, 2003, as the default browser, with Internet Explorer for Mac included only as an alternative browser. Since the release of Mac OS X v10.4 on April 29, 2005, Safari is the only web browser included with the operating system.

In June 2005, after some criticism from KHTML developers over lack of access to change logs, Apple moved the development source code and bug tracking of WebCore and JavaScriptCore to OpenDarwin.org. WebKit itself was also released as open source. The source code for non-renderer aspects of the browser, such as its GUI elements, remains proprietary.

Safari 2.0 was released on April 29, 2005, and runs only on Mac OS X v10.4.x or later; this version was touted by Apple as possessing a 1.8x speed boost over version 1.2.4.

In April 2005, Dave Hyatt, one of the Safari developers at Apple, documented his progress fixing bugs in Safari to get it to pass the Acid2 test. On April 27, 2005, he announced that his development version of Safari now passed the test, making it the first web browser to do so.The changes were not initially available to end-users unless they downloaded and compiled the WebKit source code themselves or ran one of the nightly automated builds available at opendarwin.org. However on October 31, 2005, Apple released version 2.0.2 of Safari that included the Acid2 bug fixes.

On January 9, 2007, Jobs formally announced Apple's iPhone, which uses a mobile version of the Safari browser. It now features the same JavaScript engine, "Nitro," as its desktop counterpart in iPhone OS 3.0.

Safari 3

At the 2007 Worldwide Developers Conference, Jobs announced Safari 3 for Mac OS X v10.5, Windows XP, and Windows Vista. During the announcement, he ran a benchmark based on the iBench browser test suite comparing the most popular Windows browsers, hence claiming that Safari was the fastest browser. Although third-party tests of HTTP load times suggest that Safari 3 was indeed the fastest browser on the Windows platform in terms of initial data loading over the Internet, it is actually tied with Internet Explorer 7 and Firefox when comparing loading from caches.

The initial Safari 3 beta version for Windows, released on June 11, 2007, had several known bugs and a zero day exploit that allows remote execution. The addressed bugs were then corrected by Apple three days later on June 14, 2007, in version 3.0.1 on Windows. On June 22, 2007, Apple released Safari 3.0.2 to address some bugs, performance issues and other security issues. Safari 3.0.2 for Windows handles some fonts that are missing in the browser but already installed on Windows computers, such as Tahoma, Trebuchet MS, and others. There is also a guide that allows the software to run under Linux with Wine. The final release of the Windows version, Safari 3.1, was offered as a free download on March 18, 2008.

In June 2008, Apple released version 3.1.2, addressing a security vulnerability in the Windows version where visiting a malicious web site would force a download of executable files and execute them on the user's desktop.

Safari 4

On June 2, 2008, the WebKit development team announced SquirrelFish — a new JavaScript engine that vastly improves Safari's speed at interpreting scripts. The engine is one of the new features in Safari 4, released for developers on June 11, 2008. The final revision of the JavaScript engine was marketed as "Nitro." A public beta of Safari 4 was released on February 24, 2009, with new features such as a "Top Sites" tool, similar to Opera's Speed Dial feature that displays the user's most visited sites in a 3D world. Cover Flow, a feature of Mac OS X, was also brought into Safari. While in the public beta, tabs were placed in the title bar of the window, similar to Google Chrome, the tab bar was moved back to where it used to be, below the URL bar, in the final release. For the Windows version, Safari adopted a native theme, rather than the previous Mac OS X look employed. On June 8, 2009, Safari 4 was officially released. Safari 4.0.1 was released for Mac on June 17 and fixed problems with Faces in iPhoto '09. Safari 4 in Mac OS X v10.6 "Snow Leopard" has 64-bit support, which can make Javascript loading up to 50% faster. It also has built in crash resistance unique to Snow Leopard, crash resistance will keep the browser intact if a plug-in like Flash player crashes, the other tabs or windows will be deemed unaffected.



Features

Safari offers most features common to modern web browsers such as

* Tabbed browsing
* Bookmark management
* A resizable web-search box in the toolbar which uses Google on the Mac and either Google or Yahoo! on Windows
* Pop-up ad blocking
* History and bookmark search
* Text search
* Spell-checking
* Expandable text boxes
* Automatic filling in of web forms
* Built-in password management via Keychain
* Subscribing to and reading web feeds
* Quartz-style font-smoothing
* The Web Inspector, a DOM Inspector-like utility that lets users and developers browse the Document Object Model of a web page
* Support for CSS 3 web fonts
* Support for CSS animation
* Support for Transport Layer Security protocol (version unknown)
* Bookmark integration with Address Book
* ICC color profile support
* Inline PDF viewing
* Integration with iPhoto photo management
* Mail integration
* Ability to save webpage clips for viewing on the Apple Dashboard
* Private browsing

On Mac OS X, Safari is a Cocoa application. It uses Apple's WebKit for rendering web pages and running JavaScript. WebKit consists of WebCore (based on Konqueror's KHTML engine) and JavaScriptCore (based on KDE's JavaScript engine named KJS). Like KHTML and KJS, WebCore and JavaScriptCore are free software and are released under the terms of the GNU Lesser General Public License. Some Apple improvements to the KHTML code are merged back into the Konqueror project. Apple also releases additional code under an open source 2-clause BSD-like license.

It includes a built-in web feed aggregator and supporting the standards RSS and Atom. Other features include Private Browsing (a mode in which no record of information about the user's web activity is retained) which has become the origin of the now popular term "porn mode" for web browsers), the ability to archive (using the proprietary .webarchive format) and e-mail web pages, and the ability to search bookmarks.

Beginning with Safari 4, the address bar has been completely revamped.

* The button to add a bookmark is now attached to the address bar by default.
* The reload/stop button is now superimposed on the right end of the address bar.
* The blue inline progress bar is replaced with a spinning bezel and a loading indicator attached to it.

These modifications make Safari look somewhat like Safari on iPhone.



In addition, Safari 4 includes the following new features:

* Top Sites, which displays up to 24 thumbnails of a user's most frequently-visited pages on startup
* Cover Flow browsing for History and Bookmarks
* Nitro JavaScript engine that executes JavaScript up to eight times faster than Internet Explorer 8 and more than four times faster than Firefox 3
* Native Windows look on Windows (Aero for Windows Vista, Luna for Windows XP) with standard Windows font rendering
* Support for CSS image retouching effects
* Support for CSS Canvas
* Speculative loading, where Safari loads the documents, scripts, and style information that is required to view a web page ahead of time
* Improved developer tools, including Web Inspector, CSS element viewing, JavaScript debugger and profiler, offline table and database management with SQL support, and resource graphs
* Support for HTML 5
* Completely passes the Acid3 standards test

iPhone OS-specific features

iPhone OS-specific features for Safari allow for

* MDI-style browsing (with up to 8 pages open concurrently, limited by cache storage).
* Pressing on an image for 3 seconds to save it to the photo album.
* Bookmarking links to particular pages as "Web Clip" icons on the Home screen.
* Opening specially-designed pages in full-screen mode.

System requirements

The latest version of Safari requires either a Mac, running Mac OS X v10.4.x or later, or a PC, running Windows XP SP2, Windows Vista, or Windows 7. Official minimum hardware requirements are any Intel processor or a PowerPC G3, G4, or G5 with 256MB of RAM for Mac or a 500MHz Pentium processor with 256MB of RAM. Cover Flow and Top Sites, however, requires a graphics card with 64MB or greater of video memory.

64-bit builds

The version of Safari included in Mac OS X v10.6 is now complied in 64-bit. Apple claims that running Safari in 64-bit mode will increase rendering speeds by up to 45%. However, there is currently no 64-bit build for Mac OS X v10.5 or below, Windows XP, Windows Vista, or Windows 7.

Criticism
Distribution through Apple Software Update

Apple Software Update, which is bundled with QuickTime and iTunes in Microsoft Windows, defaults to select installation of Safari even when it is not detected on a user's machine. John Lilly, CEO of Mozilla, stated that Apple's use of its updating software to promote its other products is "a bad practice and should stop." He argued that the practice "borders on malware distribution practices" and "undermines the trust that software companies are all trying to build with users." Apple has responded to Lilly's statement, saying that the company is only trying to ensure users have the latest updates to Safari, Apple also released a new version of Apple Software Update that puts new software in its own section, although still selected for installation by default. In another update, Apple Software Update no longer selects install items in the new software section by default (as of late 2008).

On September 22, 2009, Apple once again checked "Install Safari 4" as a default setting with their update to iTunes v9.0.1.

Browser exploits

In the PWN 2 OWN contest at the 2008 CanSecWest security conference in Vancouver, British Columbia, an exploit in Safari caused Mac OS X to be the first to fall in a hacking competition. Participants competed to find a way to read the contents of a file located on the user's desktop, in one of three operating systems — Mac OS X Leopard, Windows Vista SP1, and Ubuntu 7.10. On the second day of the contest, when users were allowed to physically interact with the computers (the prior day permitted only network attacks), Charlie Miller compromised Mac OS X within two minutes, through an unpatched vulnerability of the PCRE library used by Safari.

In the PWN 2 OWN contest in 2009, an as yet unidentified exploit in Safari allowed Charlie Miller to hack into a Mac in approximately 10 seconds. Apple released a patch for this exploit and others on May 12, 2009 in version 3.2.3.

End-user license agreement

The original end user license agreement for Safari on Windows was self-contradictory for several months, reading in part:

This License allows you to install and use one copy of the Apple Software on a single Apple-labeled computer at a time.

As personal computers running Windows are usually not Apple-labeled computers, with the exception of Intel-based Mac computers running Windows, it was impossible for most users of Windows to use the software and abide by the license agreement. Within hours of the story breaking, Apple changed the agreement to read:

This license allows you to install and use one copy of the Apple Software on each computer owned or controlled by you.

Updates through Apple Software Update still contained the old license.

Safari on iPhone autofill features

Autofill has been added for Safari on iPhone OS 3.0, to save the user from having to fill out forms manually. The disadvantage of this feature is that it may lead to identity theft if the iPhone is stolen and a passcode has not been set to lock the iPhone. Surfing on the ipod is limited.

Safari cache failure

Safari's cache system fails to retain large byte sized file for immediate display. Sites that have individual content such as Adobe Flash SWF files or large JPG files will not retrieve them from the browser's cache, but instead will download the content again from the server. A simple browse away from the page and an immediate return to the same page results in any large sized content to be reloaded.

http://en.wikipedia.org/