The horse fly is a large, robust insect belonging to the family Tabanidae. These flies are known for their painful bites, which they use to feed on the blood of mammals, including horses and humans. Horse flies are typically found in warm, sunny areas near water sources, where they breed in moist environments. Horse flies are characterized by their large size, with some species measuring up to 1 inch long. They have large, multifaceted eyes and a stout body, often with distinctive patterns. Unlike other flies, horse flies are strong fliers and can be quite aggressive when seeking a blood meal.