A mouse (plural: mice) is a small rodent characteristically having a pointed snout, small rounded ears, a body-length scaly tail and a high breeding rate. The best known mouse species is the common house mouse (Mus musculus). It is also a popular pet. In some places, certain kinds of field mice are locally common. They are known to invade homes for food and shelter.Domestic mice sold as pets often differ substantially in size from the common house mouse.