Mosaic is the art of creating images with an assemblage of small pieces of coloured glass, stone, or other materials. It may be a technique of decorative art, an aspect of interior decoration, or of cultural or spiritual significance.
The earliest known examples of mosaics made of different materials were found at a temple building in Mesopotamia and are dated to the 2nd half of the third millennium BC. Mosaics of the 4th century BC are found in the Macedonian city of Aegae and they enriched the floors of Hellenistic villas and Roman dwellings from Britain to Dura-Europos.
With the building of christian basilicas in the late 4th century, wall and ceiling mosaics were adapted for Christan uses. Christian mosaic art also flourished in Rome although the art gradually declined as conditions became more difficult in the Early Middle Ages.
These days the art of mosaic is once again flourishing as a popular craft - here are a few great examples of mosaic work that I have found: