ActionScript 3 for Programmers

This article is intended to be a tutorial for people who already know how to program.

Introduction
Actionscript is a language based off of ECMAscript. If you know Javascript, it's based off of the exact same specification. However, modern Javascript implementations are based off of ECMAScript 3, and Actionscript 3 is based off of a draft of ECMAscript 4. The biggest difference is the object system.

Variables
Variables are initialized using the following syntax:

var a = 2; //Without type declaration var b:Number = 2; //With type declaration

Declaring the type is completely optional, as Actionscript is a dynamic language.

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