The Apache HTTP Server, commonly referred to simply as Apache, is a
web server notable for playing a key role in the initial growth of the
World Wide Web. Apache was the first viable alternative to the
Netscape Communications Corporation web server (currently known as
Sun Java System Web Server), and has since evolved to rival other Unix-based web servers in terms of functionality and performance. Since April 1996 Apache has been the most popular HTTP server on the
World Wide Web; since March 2006 however it has experienced a steady decline of its market share, lost mostly against Microsoft Internet Information Services and the .NET platform. As of October 2007 Apache served 47.73% of all
websites.
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