- 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