Mosaic units are TILES that are used to create a mosaic. They are usually made of ceramic, stone, or glass and come in a variety of shapes and sizes. Mosaic units are often used to create decorative patterns and images on walls, floors, and other surfaces. They can also be used to create artworks, such as murals and mosaics. Mosaic units are an important part of the art of mosaic making and have been used for centuries to create beautiful works of art.