• Begin with a $
• Followed by name, starting with a letter or _underscore
• Case sensitive
• Cannot use $this, reserved for OOP
• Don't need to be declared
• Initialised at use

• Assigned with a single equals sign =

Assigned by Value

$myVar = 10 ;

$yourVar = "Potato" ;

Assigned by Reference

Prefix & ampersand to variable being referenced

$potatoVar = &$yourVar ;

Any changes to the original or referenced variable will be seen in each other. i.e. if you change one, then you change them all