Topic on Manual talk:Short URL/Apache

I have a question on the very first requirement in this guide.

Quote: "The MediaWiki directory is located at: /w"

What does this mean?

1. The mediawiki tar has been extracted in to /var/lib/mediawiki, and then a symlink named "w" has been created in /var/www/html/ to point to /var/lib/mediawiki ?
2. The mediawiki tar has been extracted in to /w . I.e. a directory called /w on the root of the server filesystem ?
3. There is no physical "w" directory on in the filesystem. There is an alias in one of the Apache config files (which one and in what section?) of the form: "Alias /w /var/lib/mediawiki"
4. Or something else?

Can this be clarified please, perhaps with an example of every place where /w is referenced so that any attempt to change it will get all of the occurrences? Thanks.

Something else: It means the tarball has been extracted into the folder /w. Later down the page we expect that this folder is located directly inside the webroot. E.g. if your webroot is /var/www, then /w would have to be /var/www/w/.