Box2DJS is a JavaScript port of the Box2D Physics Engine, and was created by Robert Kieffer. The original Box2D engine was designed as a 2D rigid body simulation library for games. Programmers are able to use it to make objects move in believable ways and make the world seem more interactive. Box2D is open source  with a strong community, numerous ports, and has been tested and deployed in many games (such as Rolando and Angry Birds). HTML5 games are an exciting new platform, and with modern JavaScript engines and hardware accelerated graphics, browsers are now capable of running more demanding gaming experiences complete with physics emulations.

The Box2D physics engine was developed by Erin Catto (visit http://www.gphysics.com for further information), who works for Blizzard Entertainment, built the library for a physics tutorial at GDC back in March 2006. It appears that the library was publicly released in Sept 2007, and a version 2.0 landed in March 2008. The 2.1 release from April 2010 included some sweeping changes. The lastest version of Box2D, 2.2, was just released in August 2011, and included performance improvements for large worlds, new joint types like wheel and rope, and many bug fixes (see the release notes).

Live demo

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