Answer:
There aren't any (at least none that I'm aware of). In PHP arrays are the same as in all other languages: variables that contain several values at different indices.
The only difference between PHP and certain other languages is the way a variable is initialised as an array:
$example = array(index => value, index2 => value2);
Contrary to other languages, this is similar to a function, as opposed to creating an instance of a class. (JavaScript for example: xyz = new Array();)