The deerfly is a type of fly belonging to the family Tabanidae. These insects are known for their large size, with some species measuring up to 1 inch long. They are typically found in wooded areas and near water sources, where they breed. Deerflies are most active during warm months and are recognized by their distinctive large eyes and patterned wings. Deerflies are notorious for their painful bites, which they use to feed on the blood of mammals, including humans. Their bites can cause irritation and allergic reactions in some individuals. Unlike other flies, deerflies are strong fliers and can be difficult to swat away.