Penrose tiles

Penrose tiles

Classic Penrose tiles consist of two rhombi with angles 72 and 36 degrees.

The edges of the rhombi are all of equal length.
classic Penrose tiles
If you follow a few strict rules about how to place them together, you’ll wind up with (= end up with) an aperiodic pattern. This means that no section of the pattern will be repeated as a unit.