PHP contains numerous functions for managing keeping track of user information, including both simple cookies and all-encompassing user sessions. Sessions use techniques built into the PHP language, making the act of saving state as easy as referencing a superglobal.
In this chapter, you will learn
How to store and retrieve cookie information
What session variables are and how they work
How to start or resume a session
How to store variables in a session
How to destroy a session
How to unset session variables