Rodentia is an order of mammals also known as rodents, characterized by a single pair of continuously growing incisors in each of the upper and lower jaws which must be kept short by gnawing.

Forty percent of mammal species are rodents, and they are found in vast numbers on all continents other than Antarctica. Common rodents include mice, rats, squirrels, porcupines, beavers, guinea pigs, and hamsters. Rodents have sharp incisors they use to gnaw wood, break into food, and bite predators. Most rodents eat seeds or plants, though some have more varied diets. Some species have historically been pests, eating seeds stored by people and spreading disease.

Rodent infestations intensify during the fall and winter as they seek to move indoors to stay warm.