What version of flash uses Actionscript 3?

I have been given a book on Actionscript 3 and I am looking to get started with learning it. What version of flash uses actionscript 3?

Also does anyone know if adobe offer trial versions of their software fo开发者_开发技巧r OSX? (10.6 snow leapard).

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Flash IDE versions CS3 and upwards can use ActionScript 3.

Flash Player 9, was the first player to support AS3 SWFs: http://en.wikipedia.org/wiki/Adobe_Flash_Player

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Flash Player 9. The first IDE to export to FP9 was CS3. But you don't need Flash to use ActionScript. You can use the open-source IDE FlashDevelop. It is hugely popular, and totally free. You will also need to get the free Adobe Flex SDK to compile to SWFs, but the install page of FlashDevelop's website gives details on everything you need, and current versions of FlashDevelop will even ask if you want it to get the SDK automatically for you.