Wingsuit flying (or wingsuiting) is the sport of flying through the air using a wingsuit, which adds surface area to the human body to enable a significant increase in lift. The modern wingsuit, first developed in the late 1990s, creates a surface area with fabric between the legs and under the arms. Wingsuits are sometimes referred to as "birdman suits" (after the makers of the first commercially available wingsuit), "flying squirrel suits" (due to their resemblance to the animal), and "bat suits" (due to their vague resemblance to the animal or perhaps the superhero).