Tessellation or tiling by M. C. Escher

Wikipedia:

"A tessellation or tiling of the plane is a pattern of plane figures that fills the plane with no overlaps and no gaps. One may also speak of tessellations of parts of the plane or of other surfaces. Generalizations to higher dimensions are also possible. Tessellations frequently appeared in the art of M. C. Escher, who was inspired by studying the Moorish use of symmetry in theAlhambra tiles during a visit in 1922. Tessellations are seen throughout art history, from ancient architecture to modern art.

In Latin, tessella is a small cubical piece of clay, stone or glass used to make mosaics.^[1] The word "tessella" means "small square" (from "tessera", square, which in its turn is from the Greek word for "four"). It corresponds with the everyday term tilingwhich refers to applications of tessellations, often made of glazed clay."

M. C. Escher's work is so diverse and amazing that it is impossible to be indifferent when someone stumble upon one of his creations."He was fascinated by mathematics:

"By keenly confronting the enigmas that surround us, and by considering and analysing the observations that I have made, I ended up in the domain of mathematics, Although I am absolutely without training in the exact sciences, I often seem to have more in common with mathematicians than with my fellow artists."

This is a key to understand his source of imagination. Still these two printings, left created in 1950 and right 1959, are fascinating and capture our eyes because they make us dream.