What is near clipping distance and far clipping distance in 3D Graphics?

Wha开发者_开发知识库t is near and far clipping distances in 3D Graphics?

If it makes a difference, I am using Ogre 3D render engine.

Near clipping distance and far clipping distance refer to the near and far plane of the viewing frustum.

Anything closer to the eye than the near clipping distance isn't displayed (it's too close), and anything further away from the eye than the far clipping distance isn't displayed either (it's too far away).