Zend has developed a section just for those out there new to the PHP language and community. In the Absolute Beginners section, they have articles on such topics as operators, form processing, using loops all the way up to creating functions and scoping variables.

I've seen a lot of places that have tried to have articles like this all in one place, but some of them haven't quite covered it all. These articles, however, seem to run the whole gamut of basic PHP knowledge. I'd definitely recommend this section of the Zend website to anyone looking to get into PHP or trying to share the world of PHP with friends/coworkers/etc.