Flash is a multimedia format developed by Macromedia. The Flash Player is a client application available in most web browsers. This allows web designers to create and develop animations and interactive movies or images, which can be embedded into a web page. Flash web designing provides a number of benefits. It features support for vector and raster graphics, a scripting language called Action Script and bidirectional streaming of audio and video. It can make a website more attractive, interactive and dynamic.

Flash technology has become a very popular method for adding animation and interactivity to web pages. Flash can show a whole company profile or presentation within a 30 second Flash. Flash can be used to create fantastic animations; to design web-page elements and also to add video to web sites. Apart from being embedded within a web page the Flash movies can also be exported to construct stand-alone executable applications.

Macromedia Flash is the integrated development environment and Flash Player is the virtual machine used to run the Flash files, but nowadays these terms have become mixed, Since a Macromedia Flash Player plug-in displays Flash movies so the Flash based work will most probably be rendered the same on all browsers and computer platforms. Flash can mean the authoring environment, the player, or the application files. The designers can escape from the constraints of more traditional XHTML based design interfaces.

Flash has come a long way since its inception. Using Flash content stores the content of the web page in a binary file and since Flash uses animations, the design of the page is not static. Flash technology has become more powerful now and its inherent potential to create more sophisticated web based applications is being appreciated by developers. These factors make Flash-based content unsuitable for indexing by search engines. Flash movies can be downloaded very easily and quickly since they can be stored in very small file sizes.

Websites made with flash can be much more interactive and flashier (pardon the pun) than site made with only normal html. Great e-learning tools and such interactive things have been coming up with small tutorials being created complete with interactive animations and self testing exercises all using flash objects. The Flash files, or "flash movies", usually have a .swf file extension and may appear as an element of a web page or to be "played" in the standalone Flash Player.