A Mosaic is a piece of art made up by little tiles or pieces of stone colored or painted to produce a painting usually placed in walls or ceilings. Mosaics have a long history, starting in Mesopotamia in the 3rd millennium BC. Pebble mosaics were made in Tiryns in Mycenaean Greece. Mosaics with patterns and pictures became widespread in classical times, both in Ancient Greece and Ancient Rome. Early Christian basilicas from the 4th century onwards were decorated with wall and ceiling mosaics.
A fresco is a technique of mural painting performed upon freshly laid or wet lime plaster. Water is used as the vehicle for the dry-powder pigment to merge with the plaster; the painting becomes an integral part of the wall.
Sculpture is the branch of the visual arts that works in three dimensions. It is one of the plastic arts. Durable sculptural processes originally used carving and modelling, in stone, metal, ceramics, wood and other materials but, since Modernism, there has been an almost complete freedom of materials and process.
Given the information I have presented, the final answer I give to this question is:
artistic techniques.
Mosaics, frescoes, and sculptures are all <u>artistic techniques.</u>
