Advantages of ActionScript 3.0
ActionScript 3.0 goes beyond the scripting capabilities of previous versions of ActionScript. It
is designed to facilitate the creation of highly complex applications with large data sets and
object-oriented, reusable code bases. While ActionScript 3.0 is not required for content that
runs in Adobe Flash Player 9, it opens the door to performance improvements that are only
available with the AVM2, the new virtual machine. ActionScript 3.0 code can execute up to
ten times faster than legacy ActionScript code.
The older version of ActionScript Virtual Machine, AVM1, executes ActionScript 1.0 and
ActionScript 2.0 code. AVM1 is supported by Flash Player 9 for backward compatibility with
existing and legacy content. For more information, see ?Compatibility with previous versions?
on page 20.
What?s new in ActionScript 3.0
Although ActionScript 3.0 contains many classes and features that will be familiar to
ActionScript programmers, ActionScript 3.0 is architecturally and conceptually different from
previous versions of ActionScript. The enhancements in ActionScript 3.0 include new
features of the core language and an improved Flash Player API that provides increased
control of low-level objects.

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