Creating a multisite website

In the past, there used to be a separate version of WordPress named WordPress MU (pronounced as myoo) that allowed you to create a master blog with many sub-blogs—essentially giving each user their own (limited) blog.

Well, as of WordPress 3.0, this capability is a built-in feature in WordPress, and just needs to be enabled. If you go to the old WordPress MU URL (http://mu.wordpress.org/), you'll see the following:

You may be wondering what makes a WordPress site, which can have multiple authors, different from a WordPress MU site. Here's the official definition from wordpress.org:

A multisite network is a collection of sites that all share the same WordPress installation. They can also share plugins and themes. The individual sites in the network are virtual sites in the sense that they do not have their own directories on your server […] and they do have separate tables in the database.

In other words, the multisite structure allows you to have a main website...