Modern triathlon wetsuits were invented by Dan Empfield in 1987 and are customized to the needs of triathletes, they generally incorporate the following key features which differentiates them from a normal wetsuit:
Thinner and/or more pliable rubber near the shoulders.
Long zippers to facilitate quick removal during transition.
In addition, tri wetsuits have a very smooth, but often fragile, surface. This slick surface helps to reduce water friction and allows a faster swim.
Another advantage of a tri wetsuit is the added buoyancy that the wetsuit provides, this can provide triathletes with a considerable speed and energy saving advantage over swimming without a suit.