Common Housefly

The housefly (also house fly, house-fly or common housefly), Musca domestica, is a fly of the suborder Cyclorrhapha. It is the most common of all domestic flies, accounting for about 91% of all flies in human habitations, and indeed one of the most widely distributed insects, found all over the world; it is considered a pest that can carry serious diseases.
The adults are 8–12 mm long. Their thorax is gray, with four longitudinal dark lines on the back. The whole body is covered with hair-like projections. The females are slightly larger than the males, and have a much larger space between their red compound eyes. The mass of pupae can range from about 8 to 20 mg under different conditions.
Like other Diptera (meaning "two-winged"), houseflies have only one pair of wings; the hind pair is reduced to small halteres that aid in flight stability. Characteristically, the media vein (M1+2 or fourth long vein of the wing) shows a sharp upward bend.
Species that appear similar to the housefly include:
The lesser house fly, Fannia canicularis, is somewhat smaller, more slender, and the media vein is straight.
Houseflies feed on feces, open sores, sputum, and moist, decaying organic matter, such as spoiled food, eggs, fruit and flesh. Houseflies can take in only liquid foods. They spit out saliva on solid foods to predigest it. They also regurgitate partly digested matter and pass it again to the abdomen.