Kevin
Joe
Audrey

How it Works

Step 1: There are five students: Kevin, Mary, Joe, Larry, and Audrey. They are assigned to the seats (variables) a, b, c, d, and e.

Step 2: Three of the student seats are put in an array: Array ( [0] => a [1] => c [2] => e )

Step 3: The array is then looped through. The key is printed out, but with two dollar signs, so seat a becomes Kevin

How it Can be Utilized

If this information were stored in a database (Kevin is in seat "a"), then a web form could be used to find out who is sitting in seat "a" and vice versa. As long as the data is stored in a string (which PHP is pretty loose about), the information can be used as a dynamic variable.