The Muridae, or murids, are the largest family of rodents and of mammals, containing approximately 1383 species, including many species of mice, rats, and gerbils found naturally throughout Eurasia, Africa, and Australia.
The name Muridae comes from the Latin mus (genitive muris), meaning "mouse," since all true mice belong to the family, with the more typical mice belonging to the genus Mus.
Murids are found nearly everywhere in the world, though many subfamilies have narrower ranges. Murids are not found in Antarctica or many oceanic islands. Although none of them is native to the Americas, a few species, notably the house mouse and black rat, have been introduced worldwide. Murids occupy a broad range of ecosystems from tropical forests to tundras. Fossorial, arboreal, and semiaquatic murid species occur, though most are terrestrial animals. The extensive list of niches filled by murids helps to explain their relative abundance.