A z-fold is a different variation of the trifold. Like the trifold, a z-fold is when a paper is folded in thirds. Z-folds are folded in the shape of a 'Z', hence the name. If you visualize the letter 'Z', the front of the brochure would be the bottom of the letter, the middle of the brochure would be the slanted part of the 'Z' between the top and bottom, and the back of the brochure would be the top of the 'Z'.