Adobe Flash (formerly Macromedia Flash) is a multimedia platform used to add animation, video, and interactivity to Web pages. Flash is frequently used for advertisements and games. More recently, it has been positioned as a tool for “Rich Internet Applications” (“RIAs”).

Flash manipulates vector and raster graphics to provide animation of text, drawings, and still images. It supports bidirectional streaming of audio and video, and it can capture user input via mouse, keyboard, microphone, and camera. Flash contains an Object-oriented language called ActionScript.

Flash content may be displayed on various computer systems and devices, using Adobe Flash Player, which is available free of charge for common Web browsers, some mobile phones and a few other electronic devices (using Flash Lite).

Originally acquired by Macromedia, Flash was introduced in 1996, and is currently developed and distributed by Adobe Systems. The precursor to the Flash application was SmartSketch, a drawing application for pen computers running the PenPoint OS developed by Jonathan Gay, who began working on it in college and extended the idea for Silicon Beach Software and its successors.

Adobe Flex is a software development kit (SDK) released by Adobe Systems for the development and deployment of cross-platform rich Internet applications based on the Adobe Flash platform. Flex applications can be written using Adobe Flash Builder or by using the freely available Flex compiler from Adobe.

The initial release in March 2004 by Macromedia included an SDK, an IDE, and a Java EE integration application known as Flex Data Services. Since Adobe purchased Macromedia in 2005, subsequent releases of Flex no longer require a license for Flex Data Services, which has become a separate product rebranded as LiveCycle Data Services. An alternative to Adobe LiveCycle Data Services is BlazeDS, an open-source project that started with code contributed in 2007 by Adobe.

In February 2008, Adobe released the Flex 3 SDK under the open source Mozilla Public License and so Flex applications can be developed using any standard IDE, for example Eclipse. There is also a commercial and proprietary IDE called Adobe Flash Builder.

Traditional application programmers found it challenging to adapt to the animation metaphor upon which the Flash Platform was originally designed. Flex seeks to minimize this problem by providing a workflow and programming model that is familiar to these developers. MXML, an XML-based markup language, offers a way to build and lay out graphic user interfaces. Interactivity is achieved through the use of ActionScript, the core language of Flash Player that is based on the ECMAScript standard.