Apache Reference: mod_auth_anon, Anonymous

Anonymous

Magic User ID for Anonymous Login
Syntax: Anonymous user [user ...]
Example: Anonymous anonymous ftp http
Since: Apache 1.1

This directive specifies one or more magic user IDs (user) that are allowed access (through HTTP Basic Authentication) without password verification. The user IDs are separated by spaces. You can use quotes or the escape character (a backslash) to insert a space in a user argument. Note that the comparison is case-insensitive. The magic user name ``anonymous'' should always be one of the allowed user IDs.