Apache is the most popular webserver on the Internet, quite possibly the best in terms of security, functionality, efficiency, and speed.
Changes: This release is primarily a security fix release, addressing a problem in mod_negotiation and mod_dir/mod_autoindex displaying a directory listing instead of the index.html.* files, if a very long path was artificially created by using many slashes. Also, it fixes some broken functionality present in the 1.3.17 release and various Win32 issues. Changelog available here.