Prefolds are a square piece of material that have a center strip of extra absorbency. You may see 4-8-4 or 2-6-2 indicators by different prefolds. This refers to the layers in each “section”. On each of the outer sides would be 4 layers and in the middle would be 8, for example. Prefolds can be fastened with pins, snappi or trifolded and laid in a cover. They also are easy to handwash and dry. Cost is very low. Prefolds are very versatile in that you can also use them as pocket stuffers.