There are many different types of mice in the world, with several hundred different species and perhaps as many subspecies. In the Western hemisphere the species are referred to as New World mice, in Europe, Asia and Africa, you’ll find Old World mice. Of course over the centuries, many species have migrated from one side of the world to the other. Still the general distinction between New World and Old World mice has tended for the most part to hold true.Some of the more commonly encountered types of mice are assigned specific names, the common deer mouse being an example. Other types are simply referred to as brown mice, black mice, house mice, field mice, and so on. What one person calls a particular species of mouse, may be something completely different from how another person refers to that same species.