Imagine a grid of squares -- like a piece of graph paper. Each grid can be be subdivided to create more grids, but the basic framework of the initial grid remains the same. Patchwork quilt blocks are exactly the same, and with a little practice you'll instantly recognize their structure.
Four Patch Quilt BlocksFour-patch quilt blocks are one of the most common in patchwork quilts. They initially contain four equal squares arranged in a grid of two across and two down. You can see that basic grid in the left and middle illustrations above.
Four patch grids in the block on the right have been subdivided, but the block's original four-patch structure is still recognizable. You'll find that most four-patch quilt blocks have subdivided units. Take a look at some of the patterns below to see if you recognize their original grid.