The Brown Rat or Norway Rat is one of the best-known and common rats, and also one of the largest. It is not known for certain why it is named Norwegian rat since it does not originate from Norway. It lives wherever humans live, particularly in urban areas.

The Norway Rat will consume almost anything, but with cereals forming a substantial part of the diet. They are usually active at night and are good swimmers, both on the surface and underwater, but are poor climbers. They dig well, and often excavate extensive burrow systems.

The fur is coarse and usually brown or dark grey, the underparts are lighter grey or brown. The length can be up to 16 in., with the tail a further 10 in. (the same as the body length). Adult body weight averages 1 lb. in males and about 8 oz. in females, but a very large individual can reach 1.3 lbs.

Norway Rats are supposed to carry some diseases, including Weil's disease, cryptosporidiosis, Viral hemorrhagic fever (VHF), Q fever and hantavirus pulmonary syndrome. Unlike the Black Rat, Norway Rats rarely if ever carry bubonic plague.

The Black Rat, also known as the Asian Black Rat, Ship Rat, Roof Rat or House Rat, is a common long-tailed rodent.

A typical rat will be 6 to 8 in. long with a further 8 in. of tail. It is nocturnal and omnivorous, with a preference for grains. In a suitable environment it will breed throughout the year, with a female producing three to six litters of up to ten young

Despite its name it comes in several colour forms. Compared to the Brown Rat, it is a poorer swimmer, but more agile and a better climber, tending even to flee upwards. It is usually black to light brown in colour with a lighter underside.

The best known mouse species is the common house mouse. It is found in nearly all countries.

Light brown or light grey in color, the house mouse is small and slender with large ears and small eyes. They have a keen sense of hearing, taste, smell and touch. While they are mostly active at night they can be seen during the day searching for food.

Although they usually feed on cereal grains, they will eat almost anything. They nest within structures or burrows and establish a "territory" near food sources, generally 10 to 30 feet from their nest. The house mouse is a prolific breeder.

Mice can be harmful pests, damaging and eating crops and spreading diseases through their parasites and feces. The original motivation for the domestication of cats is thought to have been for their predation of mice and their relatives, the rats.

The Field Mouse is a cousin to the rat and the two share certain attributes. For instance the coloring of these rodents are similar, blacks browns and whites, although more commonly mice will be more white or grey than others.

Field Mice do not share the large front teeth of rats and their claws are much smaller. A full grown Field Mouse is between 4 to 8 in. long. The tail is usually as long as the body and is completely hairless. It has extremely small, though sharp claws attached to its stubby legs.

Field Mice are scavengers. They will eat anything they think they can. They occasionally dig through homes at the scent of food and stay there for the shelter inside the walls. Most buildings are home to at least one Mouse which quietly eats whatever it can before escaping to its home. The Field Mouse is nocturnal.