The breaststroke is without a doubt one of the most popular swimming strokes. In fact, many recreational swimmers are perfectly happy using this swim stroke all the time. Because it is so popular, we consider it as one of the basic swimming strokes.
The front crawl or forward crawl, also known as the Australian crawl or American crawl, is a swimming stroke usually regarded as the fastest of the four front primary strokes. As such, the front crawl stroke is almost universally used during a freestyle swimming competition, and hence freestyle is used metonymically for the front crawl.
The butterfly stroke is one of the most difficult swimming strokes. It is sometimes referred to as "Fly" for short. Although it is the second fastest stroke when done properly by a skilled athlete, it requires a very exact technique, strength and rhythm.
The freestyle stroke, also known as front crawl, is the fastest and most efficient of the competitive swimming strokes. That’s why it is always used in the freestyle event of swimming competitions and is also often the preferred stroke of experienced swimmers and triathletes.