#! code

Drupal is a CMS system that can be freely downloaded and used from the Drupal website. It is not an object orientated PHP driven system and so everything is available through function calls and variables.

Regular expressions are a very useful tool for any programmer wanting to validate input, format strings, change words, reformat data or even split apart a string into an array. However, when you are starting out, writing them it can be hard going, they are not very easy to learn and the only way to really understand them is to practice, practice, practice.