What is Adobe Flash Player?

The Adobe Flash Player is software for viewing multimedia, Rich Internet Applications and streaming video and audio, on a computer web browser or on supported mobile devices. Flash Player runs SWF files that can be created by the Adobe Flash authoring tool, by Adobe Flex or by a number of other Macromedia and third party tools. Flash Player was created by Macromedia and now developed and distributed by Adobe Systems after its acquisition. Flash Player supports vector and raster graphics, 3D graphics, an embedded scripting language called ActionScript and streaming of video and audio. ActionScript is based on ECMAScript, and supports object-oriented code, and may be compared to JavaScript. Flash Player has a wide user base, with over 90% penetration on internet connected personal computers,and is a common format for games, animations, and GUIs embedded into web pages.

Flash Player is freely available as a plugin for recent versions of web browsers (such as Internet Explorer, Mozilla Firefox, Opera, and Safari) on selected platforms. Google Chrome integrated the player into the distribution. Each version of the plugin is backwards-compatible.

Flash Player is used internally by the Adobe Integrated Runtime (Adobe AIR), in order to provide a cross-platform runtime environment for desktop applications and mobile applications. The runtime supports installable applications on Windows, Linux, Mac OS, and some mobile operating systems such as iOS and Android. Flash applications must specifically be built for the Adobe AIR runtime in order to utilize additional features provided, such as file system integration, native client extensions, native window/screen integration, taskbar/dock integration, and hardware integration with connected Accelerometer and GPS devices.
from wikipedia