Free themes are designed to be as easy to install as possible. You simply upload your theme, activate it, and you’re done. It knows your blog’s name, description, feed URL and everything else.

In order to know all of this, the theme uses PHP tags to get the information. However, it has to use these tags every time a page is loaded.

As most of the information never changes, you can delete these tags from your theme, and replace them with normal text. That way, your server has less to process next time around.