Using Permalinks « WordPress Codex

Using Permalinks « WordPress Codex: "Using "Pretty" permalinks
Requirements:

Apache web server with the mod_rewrite module installed
In WordPress's home directory,
The FollowSymLinks option enabled
FileInfo directives allowed (e.g. AllowOverride FileInfo or AllowOverride All)
An .htaccess file (if this file is missing, WordPress will try to create it when you activate "pretty" permalinks)
If you want WordPress to update the .htaccess file automatically, WordPress will need write access to the file.
For lighttpd, see below."

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