This is the software publisher's description.

Adobe's Flash Player 9 is the next-generation Flash Player client runtime environment.

Flash Player provides a more secure, lightweight, robust runtime environment for rich media and enterprise-ready rich internet applications.

Flash Player 9 achieves up to 10 times faster performance through ActionScript 3.0 and a new ActionScript Virtual Machine, which features a Just In Time compiler that translates ActionScript bytecode to native machine code for maximum execution speed.

Installed on over 600 million internet-connected PCs and mobile devices worldwide, Flash Player provides consistent and predictable application runtime capabilities across browsers, desktops and other devices.

Flash Player and Adobe Reader provide client runtime capabilities for the Adobe Engagement Platform, which delivers a programming model, tools, components and services that enable designers and developers to create and deliver rich, vibrant, branded content and applications to mass audiences in virtually every medium.

This version is for Mozilla Firefox, Opera, Netscape web browsers. A version for Internet Explorer is also available.

The latest version is a preview release and now supports H.264 video, so you can play non-DRM iTunes videos, podcasts and embed HD video on your website, playable via Flash player.