Introduction to PHP Regular Expressions (#1): General Mechanics

Anyone that has to do a large sum of unusual data manipulation will always choose to use regular expressions ('regex') over native functions because of one thing: power. In PHP the 'ereg_' functions are what utilize ERE POSIX, and the 'preg_' functions utilize PCRE. In this 'introduction to regular expressions' the author will assume no prior knowledge of regex, and will try to give you the most thorough explanation of this powerful tool as possible.