The housefly (also house fly or house-fly), Musca domestica, is the most common fly occurring in homes and indeed one of the most widely distributed animals and the most familiar of all flies; it is a pest that can facilitate serious diseases.
Flies continually preen themselves, cleaning their eyes with their forelegs and dusting off their legs by rubbing them together. They do this because most of their taste and smell receptors are on the hairs of their legs.Houseflies can take in only liquid foods. They spit out saliva on solid foods to pre-digest it, and then suck it back in. They also vomit partially digested matter and eat it again.
The flies can walk on vertical planes, and can even hang upside down from ceilings. This is accomplished with the surface tension of liquids secreted by glands near their feet.