The word tessellation may sound scholarly and forbidding. It's not. Tessellating is as simple as tiling a floor.
This is a tessellation.
A tessellation is a pattern that uses a single repeated shape to completely cover a surface without gaps.
If we forget about floors and think about quilts, then a whole new world of quilt design opens up to us.
Playing with Tessellation
What if I create a block on a nine-patch grid that looks like this? Can I use it to make a tessellation?
This won't tessellate because it consists of 2 different shapes and tessellations must have only one repeated shape. Can I change it so that it will tessellate?
It does. The black and grey areas are identical, so only one shape is being repeated.
The tessellation is more apparent when the block is repeated, as in these 2 examples.