PHP Tutorials REGULAR EXPRESSIONS Web development always requires you to manipulate a lot of text. PHP string functions give you the ability to manipulate text but sometimes some manipulations get very complicated. Regular expressions (regex) give you more power and control than the normal string functions. On this tutorial we are going to review the use of PCRE’s or Perl Compatible Regular Expression. My First PHP Script In this tutorial you will learn to make a very basic php script. It will show you what is needed and some tips for beginners.