PhysX is a proprietary realtime physics engine middleware SDK. PhysX was authored at NovodeX, an ETH Zurich spin-off. In 2004 NovodeXwas acquired by Ageia, and in February 2008 Ageia was acquired by Nvidia. The term PhysX can also refer to the PPU expansion card designed by Ageia to accelerate PhysX-enabled video games. Middleware physics engines free game developers from writing own code which implements classical mechanics (Newtonian physics) to do e.g. soft body dynamics. PhysX is one of the handful of physics engines used in the large majority of today's games.