How to install Blender 2.63 in Ubuntu 11.04/11.10/12.04

Blender is a free and open-source 3D computer graphics software product used for creating animated films, visual effects, interactive 3D applications or video games. Blender's features include 3D modeling, UV unwrapping, texturing, rigging and skinning, fluid and smoke simulation, particle simulation, animating, match moving, camera tracking, rendering, video editing and compositing. It also