Pixels and voxels, the long answer
A Pixel Is Not A Little Square, A Pixel Is Not A Little Square, A Pixel Is Not A Little Square! (And a Voxel is Not a Little Cube) [1]<p>[1] <a href="http://alvyray.com/Memos/CG/Microsoft/6_pixel.pdf" rel="nofollow">http://alvyray.com/Memos/CG/Microsoft/6_pixel.pdf</a>