Flash

Flash enables interactive features on websites, including animation, videos, and other multimedia experiences.

Technically, Flash has 2 meanings:
1. Flash is short for Adobe Flash, the industry-standard animation program used to create interactive features on websites, including animation, videos, and other multimedia features. Adobe Flash was called Macromedia Flash from 1996- 2007, by which time Adobe had purchased Flash from Macromedia. Adobe Flash was first known as FutureSplash Animator, and was initially designed primarily for animation. By November 1996, FutureSplash Animator had changed its name: the "F" from "Future" and the "-ash" from "Splash" were combined into the new name "Flash." As early as 1998, Flash included the ability to integrate short movie clips into website programming.
2.  Flash can also refer to the Adobe Flash Player, open source software plug-in that allows Internet users to view Flash-generated features, such as videos (on YouTube), rich internet applications, animation (including websites and advertisements), and other multimedia features. Adobe Flash Player is built into some web browsers. It is compatible with most major operating systems, including Microsoft Windows, Mac OS X, Pocket PC, Solaris, and Linux.