A small part of The Great Pavement at Woodchester, Gloucestershire, England. The 48 ft by 48 ft (15 m by 15 m) Roman mosaic uses 1.5 million 0.5 inch (12 mm) square pieces of stone. Once the floor of a Roman villa, it was laid around AD 325.
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A mosaic is a form of decorative art, in which small tiles or fragments of pottery (known as tesserae, diminutive tessellae) are used to create a pattern or picture.

It was used in ancient times for domestic interior decoration. Mosaics are particularly associated with Roman dwellings, for example on floors; but the craft has continued through the ages, and many modern examples exist. M.C. Escher was influenced by Moorish mosaics to begin is investigations into tessellation.