A quilt is basically 3 layers. The top layer of fabric(pieced or whole) and middle batt (quilt batt,old flannel blanket etc.) and the bottom or back layer of fabric. These 3 layers are attached together to make a quilt. You can attach these 3 layers together in a number of ways. You can stitch lines down it by machine, you can tie yarn or string in spots to anchor the 3 layers together, you can sew buttons through the layers, you can hand stitch the layers together etc. etc. This is the most basic definition of a quilt and all other quilts are variations on this 3 layer sandwich. You might like to look at the Gee's Bend quilts for example of quilts made from what the people had on hand before all the great supplies we enjoy today.