Wordpress is the free, wildly popular blogging platform that millions of bloggers use to power their blogs. Many web hosts offer a quick install script for Wordpress that will allow you to have a blog set up and ready to receive fresh content in about 10 minutes or less.
Wordpress MU, with the MU standing for multi-user, used to be a separately developed solution for setting up a network of blogs which allowed blogs to have multiple users each with their own dashboard and theme. But since...