here is the simple example for declaring variables:

<?php
$txt="Hello World!";
$x=16;
?>

Thank u,

Regards
Srikanth
rxonlineshopee.com

some of Note for declare a variable
variables in PHP start with a dollar sign ($)
variables' names are case sensitive
you can use alphanumeric characters and underscores (no spaces)
the first character of a string name can be a letter or an underscore (no numbers)
you can assign a value to a variable using the assignment operator (=)
you cannot name a variable $this
if the value is a piece of text (a string) you have to wrap the value in between quotation marks
if the name of the variable contains more than one word, please use lower camel case notation (e.g. $thisIsMyName or $varNameHere)