Microsoft Internet Explorer is a web browser application created by Microsoft primarily for Microsoft Windows. It was initially based on Spyglass Mosaic. At various points, Internet Explorer was also available for MacOS, Solaris, and HP-UX.
At its 1995 release, Internet Explorer competed with the Mosaic web browser and Netscape Navigator. Home Internet access was still somewhat new and competed against proprietary services like CompuServe, AOL, and Microsoft's own MSN.
Microsoft aggressively and abusively positioned Internet Explorer as part of their "browser war" to eliminate all competition. Microsoft fiercely pushed third party products to bundle Internet Explorer, and web sites to work only in Internet Explorer.
In 1998, Microsoft was hit with an antitrust suit, much of which involved their browser bundling.
By around 2004, Microsoft had destroyed most of their competition, dominated the browser market, and let IE stagnate until Mozilla.org released Firefox.
After Internet Explorer 11, Microsoft supplanted IE with "Microsoft Edge" which eventually switched to the Google Chrome rendering engine. Something that would have been unthinkable back then.
Internet Explorer is freely redistributable. But is archived here, as much software (stupidly) requires it.
With version 4, Microsoft began referring to IE as an "operating system component". IE 4 was bundled with Windows 98 First Edition, and Windows 95 OSR 2.5. IE 4 32-bit supported 95 and NT 4. IE 4 was also made avaliable for HP-UX and Solaris, built with ported Windows libraries.
Microsoft did not allow users to uninstall IE 4 from Windows 98. Microsoft claimed removal was impossible but a product called 98Lite did exactly that.
Shortly before the release of IE 4, Apple was forced to bundle IE for Mac as the default browser instead of Netscape. Otherwise Microsoft would not continue to produce MS-Office for the Mac. Steve Jobs was BOOED as he announced IE would be the default browser.
With Internet Explorer 4 and Windows 98 Microsoft included an "Integrated Desktop". It used the IE shell for file windows, and could display a web page as the desktop. Because, obviously, that must be useful somehow. This had the effect that Microsoft Internet Explorer was running at all times, and stole memory and visibility from Netscape.
IE 4 was a non-optional component of many Microsoft and third party software programs.
Also of note: Internet Explorer 4 added a setup manager, a small executable for users to download that in turn downloaded only the required components from Microsoft's site. Therefore many downloaded copies may be incomplete. Too often, idiots would save just the setup stub to a floppy or CD, not realizing the actual software had to be downloaded separately.
First, draw a pentagram on the floor...