Session Variable in PHP - How To Use It - An introductory tutorial

The session variable is inbuilt to php and allows programmers to access it from any page at any time. The session persists for the duration of the user's visit.

Rather than use the post array or get array that only passes information from one page to another, the session array allows users to carry variables of any datatype across the entire session without the need to keep passing items over and over again.