ActionScript was initially designed for controlling simple 2D vector animations made in Adobe Flash (formerly Macromedia Flash). Later versions added functionality allowing for the creation of Web-based games and rich Internet applications with streaming media (such as video and audio).

History

ActionScript started as a scripting language for the Macromedia Flash authoring tool. The first three versions of the Flash authoring tool provided limited interactivity features. Early Flash developers could attach a simple command, called an "action", to a button or a frame. The set of actions was limited to basic navigation controls, with commands such as "play", "stop", "get URL", and "goto and play".

With the release of Flash 4 in 1999, this simple set of actions matured into a small scripting language. New capabilities introduced for Flash 4 included variables, expressions, operators, if statements, and loops. Although referred to internally as "ActionScript", the Flash 4 user manual and marketing documents continued to use the term "actions" to describe this set of commands.

Time line by player

Flash Lite 1.0 and 1.1: Flash Lite is the Flash technology specifically developed for mobile phones and consumer electronics devices. Flash Lite 1.1 supports Flash 4 ActionScript.
Flash Lite 2.1: Added support for Flash 7 ActionScript 2.0.
Flash Player 2: First version with scripting support, actions included gotoAndPlay, gotoAndStop, nextFrame and nextScene for timeline control.
Flash Player 3: Expanded basic scripting support with the ability to load external SWFs (loadMovie).
Flash Player 4: First player with a full scripting implementation (called Actions). The scripting was a slash based syntax and contained support for loops, conditionals, variables and other basic language constructs.
Flash Player 5: Included the first version of true ActionScript. Used Prototype-based programming based on ECMAScript, and allowed full Procedural programming and Object-Oriented programming.
Flash Player 6: Added an event handling model, and support for switch.
Flash Player 7: Flash Player 7 offered some new features such as CSS text and performance improvements. Macromedia Flash compilers released alongside Flash Player 7 also support ActionScript 2.0, a Class programming language based on the ECMAScript 4 Netscape Proposal. However, ActionScript 2.0 can cross compile to ActionScript 1.0 byte-code, so it can be run by Flash Player 6.
Flash Player 8: Further extended ActionScript 2.0 by adding new class libraries with APIs for controlling bitmap data at run-time, and file-upload.
Flash Player 9 (initially called 8.5): Added ActionScript 3.0 with the advent of a new virtual machine, called AVM2 (ActionScript Virtual Machine 2), which coexists with the previous AVM1 needed to support legacy content. Performance increases were a major objective for this release of the player including a new JIT compilation. This is the first release of the player to be titled Adobe Flash Player