Basically, this
idea is to bring two
points in
space closer together (
folding space) in some way so that you can travel between them quickly without having to travel faster than
light. This would make the time to travel between two points basically instantaneous.
Example
Think of space in the simplest of fashions, a sheet of paper. Draw two points on this sheet of paper, one at the bottom and one in the middle of the page. Now imagine that you are at the point at the bottom of the page, and you need to get to the point in the center of the page (remember the page represents space), but you need to get there in the fastest and shortest manner. The fastest way to get to that point is to take the paper and fold it so that the point you are trying to get to is basically on top of the point you are currently at. You have now successfully shortened the distance between the points, thusly folding space so that you can travel almost instantaneously to your destination.