PHP is a scripting language primarily used for web development. Omeka is written in PHP, using the Zend Framework.
Resources
- PHP.net - The official site of the PHP project.
Web Tutorials
Books
There are plenty of books about PHP. A few suggestions:
- Sams Teach Yourself PHP, MySQL and Apache All in One (4th Edition) by Julie Meloni.
- PHP for the World Wide Web, Third Edition by Larry E. Ullman