What Is Microsoft Internet Explorer
Microsoft Internet Explorer is a discontinued web browser developed by Microsoft, first released in 1995 as part of the Windows operating system. It was once the dominant browser, peaking at over 95% market share in the mid-2000s before declining due to competition from Firefox, Google Chrome, and Safari. The browser was officially retired on June 15, 2022, with Microsoft recommending its successor, Microsoft Edge, for all users. According to data from StatCounter, Internet Explorer held less than 1% of global browser usage by the end of its lifecycle. For more details on the retirement timeline, see the official Microsoft lifecycle FAQ Microsoft Internet Explorer 11 retirement FAQ.
The browser was deeply integrated into Windows, serving as the default rendering engine for many enterprise applications and intranet sites. Its Trident engine powered countless legacy web applications throughout the 2000s and early 2010s. Microsoft eventually shifted its strategy to the Chromium-based Edge browser, which offered better performance and modern web standards compliance. This transition marked a significant shift in Microsoft's browser strategy, moving away from its proprietary engine to an open-source foundation. The shift is documented in Microsoft's official blog announcement The future of Internet Explorer on Windows 10 is in Microsoft Edge.
Key Features and Technical Specifications
Internet Explorer supported technologies like ActiveX, VBScript, and proprietary Microsoft extensions that shaped early web development. Its final version, Internet Explorer 11, introduced improved JavaScript performance, hardware acceleration, and support for modern CSS features. The browser included a built-in PDF viewer, tracking protection lists, and a compatibility view for legacy sites. It was the last version to support Windows 7 and Windows Server 2008 R2, extending its reach in enterprise environments. For a technical deep dive into the final release, see the Internet Explorer 11 documentation IE11 developer guide.
The browser's user interface evolved over time, introducing features like tabbed browsing, a favorites center, and a streamlined command bar. Internet Explorer 11 also included Enterprise Mode, which allowed organizations to render legacy sites in an older document mode while using modern standards for new sites. This feature was critical for businesses relying on older web applications that were incompatible with modern browsers. The mode is documented in the Enterprise Mode documentation What is IE mode in Microsoft Edge.
Legacy, Market Impact, and Alternatives
Internet Explorer's decline accelerated after 2010, driven by the rise of mobile browsing and the superior performance of competitors. Its market share fell from dominance to single digits as users migrated to faster, more standards-compliant alternatives. Microsoft's own data showed that Edge captured a growing share of the Windows browser market after its 2015 launch, further marginalizing Internet Explorer. The browser's end-of-life forced many enterprises to migrate legacy applications to modern standards or use virtualization solutions. The impact on enterprise software is discussed in industry analyses from ZDNet Microsoft Internet Explorer end of life: what you need to know.