Do flies bite pinch or sting?

Flies (and fleas) bite. Bees and wasps sting. The flies that bite include deer flies, horse flies, midges, and others.

The best way to kill a horsefly when it lands on you is to watch and wait. When it first lands, it watches to see if you are going to swat at it. If you don't, it will put its head down to bite and draw blood. As soon as it moves its head, its focus is on your skin, and you can kill it much more easily.