Scratch

Scratch is a visual programming language. It can be accessed as a free desktop and online multimedia authoring tool that can be used by students, scholars, teachers, and parents to easily create games and provide a stepping stone to the more advanced world of computer programming. It can also be used for a range of educational and entertainment constructionist purposes from math and science projects, including simulations and visualizations of experiments, recording lectures with animated presentations, to social sciences animated stories, and interactive art and music.Viewing the existing projects available on the Scratch website, or modifying and testing any modification without saving it requires no online registration.

Scratch users to use event driven programming with multiple active objects called "sprites". Sprites can be drawn as either vector or bitmap graphics from scratch in a simple editor that is part of the Scratch, or can be imported from external sources, including webcams.

Scratch 2 is currently available online and as an application for Windows, Mac OS X and Linux.The source code of Scratch 1.x is made available under GPLv2 license and Scratch Source Code License.

A spinoff of the Scratch programming language is also used in the game creation tool Stencyl.

Exerpt taken from Wikipedia