# Runtime considerations of ActionScript 2

During compilation, classes and interfaces you define with ActionScript 2 are compiled into ActionScript 1 syntax. The runtime equivalent of a class is an object in the `_global` namespace. The package that a class belongs to further determines its namespace. For example, consider the following ActionScript 2 class definition:

    class myClass extends mySuperClass {

    	// Property
    	var myProp:String = "Hello, world";

    	function myClass() {
    		// constructor function
    	}
    }

When this code is compiled (for Flash Player 6 or later) it is translated into something like the following:

    _global.myClass