Variables in PHP

Variables in PHP are represented by a dollar sign followed by the name of the variable. The variable name is case-sensitive.

Variable names follow the same rules as other labels in PHP. A valid variable name starts with a letter or underscore, followed by any number of letters, numbers, or underscores. As a regular expression, it would be expressed thus: '[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*'

Note: $this is a special variable that can't be assigned.


<?php
$var = 'Bob';
$Var = 'Joe';
echo "$var, $Var"; // outputs "Bob, Joe"

$4site = 'not yet'; // invalid;…