A rat is a small rodent found on all continents except Antarctica. In the wild, rats are often considered to be pests. They may be associated with the transmission of disease. Infected fleas living in the fur of rats are supposed to have spread bubonic plague. The genus Rattus includes over 50 species.
Rats are capable of surviving in a wide range of different environments ranging from grasslands, forests, urban settlements, ships, and the unforgiving arctic. They tend to thrive around human beings.
Rats can make good pets. They are usually kept in a cage or a terrarium, sometimes with other rats or mice. Domestic rats are curious, clean, and gentle creatures with a life-span of approximately three years.