Name

Alias

Synopsis

Alias url_path directory_or_filename
Server config, virtual host

Alias is used to map a resource’s URL to its physical location in the filesystem, regardless of where it is relative to the document root. For instance, see .../site.alias/conf/httpd.conf:

...
Alias /somewhere_else/ /usr/www/APACHE3/somewhere_else/
...

There is a directory /usr/www/APACHE3/somewhere_else/, which contains a file lost.txt. If we navigate to www.butterthlies.com/somewhere_else, we see:

Index of /somewhere_else
    Parent Directory 
    lost.txt