UserDir directive
Syntax: UserDir directory-filename
Default: UserDir public_html
Context: server config, virtual host
Status: Base
Module: mod_userdir
Compatibility: All forms except the UserDir public_html form are only available in Apache 1.1 or above. Use of the enabled keyword, or disabled with a list of usernames, is only available in Apache 1.3 and above.

A request for http://www.foo.com/~bob/one/two.html will be translated to:

UserDir public_html -> ~bob/public_html/one/two.html
UserDir /usr/web -> /usr/web/bob/one/two.html
UserDir /home/*/www -> /home/bob/www/one/two.html

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questo e molto altro nella documentazione di apache