Internet Explorer shell

An Internet Explorer shell is any computer software that uses the Trident rendering engine of the Internet Explorer web browser. Although the term "Trident shell" is probably more accurate for describing these applications (including Internet Explorer itself), the term "Internet Explorer shell", or "IE shell", is in common parlance. This means that these software products are not actually full-fledged web browsers in their own right but are simply an alternate interface for Internet Explorer; they share the same limitations of the Trident engine, typically contain the same bugs as IE browsers based on the same version of Trident, and any security vulnerabilities found in IE will generally apply to these browsers as well. Strictly speaking, programs that use Tasman (layout engine), used in Internet Explorer 5 for Apple Mac, are also IE shells, but, because Internet Explorer for Mac was discontinued in 2003, and Tasman was further developed independent of IE, it tends to be thought of as a separate layout engine.

These applications supplement some of Internet Explorer's usual user interface components for browsing, adding features such as popup blocking and tabbed browsing. For example, MSN Explorer can be considered an Internet Explorer shell, in that it is essentially an expansion of IE with added MSN-related functionality. A more complete list of Trident-based browsers can be found under the list of web browsers.

Other applications that are not primarily for web browsing, such as Intuit's Quicken and QuickBooks, AOL, Winamp, and RealPlayer, use the rendering engine to provide a limited-functionality "mini" browser within their own user interfaces.

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