The common housefly is usually less than 1\4 inch in length and has a blackish gray body with black stripes running the length of its body. The lesser housefly is a bit larger with a blackish gray body and yellow stripes. The face fly has a close resemblance to the housefly but it slightly larger. The body of this fly is blackish gray with sparse yellow hairs. When resting the face fly will overlap its wings on its back. The common housefly and lesser housefly rest with both wings slightly spread to the sides. All three species have mouths that are made for sucking or lapping and are unable to bite. Even so, their buzzing and habit of lighting on anything available tend to make them quite an annoying pest.

Most houseflies are considered to be nasty little creatures. This is because of their habit of visiting such areas as garbage, manure piles, compost and such. It is true that they carry microscopic organisms that can be unhealthy. In most cases these organisms are found on their feet.

Houseflies spend the winter months as adults, making any warm area their home. When spring arrives they emerge and the fertile females deposit their eggs in rotted or decaying materials. Each female will deposit no less than 100 eggs that will hatch in around one day. The larva of the housefly, commonly called maggots, will pupate for almost a week before becoming adults. In warm areas it is not uncommon for the female housefly to produce up to ten broods each year. Interestingly, houseflies have become immune to many of the pesticides used by man to destroy them.