Warped Discs?

I was reading in the Ps3 instruction manual that, "stacking discs at an angle can cause them to warp". What is warping, how does it happen, and what does it do to the game?

I was reading in the Ps3 instruction manual that, "stacking discs at an angle can cause them to warp". What is warping, how does it happen, and what does it do to the game?

Cheesemanook

You'll know if warping occurs because the game case itself will be the first to warp. If you'll notice signs of warping on the case. Relocate your game collections immediately to a cool dry place before it affects the game disk.

thanks for the info, not that I have any warped discs, I was just curious as to what it is.