History

Internet Explorer was originally derived primarily from Spyglass Mosaic, an early commercial proprietary web browser. In 1996, Microsoft licensed Spyglass Mosaic from Spyglass for a quarterly fee plus a percentage of Microsoft's revenues for the software. Although bearing a name similar to NCSA Mosaic, which was the first widely used browser, Spyglass Mosaic was relatively unknown in its day and used the NCSA Mosaic source code only sparingly.[1]

Internet Explorer was not widely used until the release of version 3, which was the first version developed without Spyglass sources (although still using Spyglass "technology", so the Spyglass licensing information remained in the program's documentation). Internet Explorer 4 was the first version integrated into Windows Explorer and other core parts of Windows. The integration with Windows, however, was subject to numerous criticisms (see United States v. Microsoft).

Internet Explorer 3 was the first major browser with CSS support. Released on August 13, 1996, it introduced support for ActiveX controls, Java applets, inline multimedia, and the PICS system for content metadata. These improvements were significant, compared to its main competitor at the time, Netscape Navigator. Version 3 also came bundled with Internet Mail and News, NetMeeting, and an early version of the Windows Address Book, and was itself included with Windows 95 OSR 2. Version 3 proved to be the first popular version of Internet Explorer, which brought with it increased scrutiny. In the months following its release, a number of security and privacy vulnerabilities were found by researchers and hackers.

Version 4, released in September 1997, deepened the level of integration between the web browser and the underlying operating system. Installing version 4 on a Windows 95 or Windows NT 4 machine and choosing "Windows Desktop Update" would result in the traditional Windows Explorer being replaced by a version more akin to a web browser interface, as well as the Windows desktop itself being web-enabled via Active Desktop. This option was no longer available with the installers for later versions of Internet Explorer but was not removed from the system if already installed. Internet Explorer 4 introduced support for Group Policy, allowing companies to configure and lock down many aspects of the browser's configuration. Internet Mail and News was replaced with Outlook Express, and Microsoft Chat and an improved NetMeeting were also included. This version also was included with Windows 98.

Version 5, launched on March 18, 1999, and subsequently included with Windows 98 Second Edition and bundled with Office 2000, was another significant release that supported bi-directional text, ruby characters, XML, XSL and the ability to save web pages in MHTML format. (Windows 2000 included Internet Explorer 5.01 instead.) Version 5.5 followed in July 2000, improving its print preview capabilities, CSS and HTML standards support, and developer APIs; this version was bundled with Windows Me.

Version 6 was released on August 27, 2001, a few weeks before Windows XP. This version included DHTML enhancements, content restricted inline frames, and partial support of CSS level 1, DOM level 1 and SMIL 2.0. The MSXML engine was also updated to version 3.0. Other new features included a new version of the IEAK, Media bar, Windows Messenger integration, fault collection, automatic image resizing, P3P, and a new look-and-feel that was in line with the "Luna" visual style of Windows XP. In 2002, the Gopher protocol was disabled and support for it was dropped in Internet Explorer 7