Mosaics were used in a variety of private and public buildings across the Roman Empire. They were influenced by earlier and contemporary Hellenistic mosaics, and often included famous figures from history and mythology.
2. Judgment of Paris, c. 115–150 AD; from the Atrium House, Antioch-on-the-Orontes. Louvre. (c) Mbzt
3. Amazon warrior engaged in combat, 4th c. AD. Louvre. (c) Marie-Lan Nguyen
4. Theseus killing the Minotaur from Pompeii. Naples Archaeological Museum.
5. Ulysses and the Sirens. Bardo Museum.
6. Centaur from Hadrian’s Villa. Altes Museum, Berlin.
They also give the viewer an insight into everyday life in the Roman Empire; the activities they partook in, the food they ate, the clothes they wore and also a glimpse of the natural world around them.
Unswept floor. Vatican Museum. 
Marine life from Pompeii. Naples Archaeological Museum. 
Actors from the House of the Tragic Poet. Naples Archaeological Museum. 
Gladiators from the Zilten mosaic. Tripoli. 
Dominus Julius mosaic. Bardo Museum. (c) O. Mustafin
Mosaics, also known as opus tessellatum, were made from small squares of cut marble, tile, glass, pottery, stone and shells, called tesserae.
A popular style in Roman Italy was to use just black and white tesserae, especially in marine motifs designed for Roman bath complexes, such as at Ostia and the Baths of Caracalla in Rome.
Baths of the Coachmen, Ostia. (c) ostiaantica.org 
Baths of Caracalla, Rome. (c) Jona Lendering 
Square of the Corporations, Ostia. (c) ostiaantica.org
Digital Maps of the Ancient World 