A fish is a short, wide surfboard with flat rocker in the nose and tail. The modern fish, also known as the rocket fish has three or sometimes five fins. However, the original 1970s 'retro' fish was designed with large twin keel fins. Fish surfboards catch waves surprisingly well despite their lack of surface area (most fishes are significantly shorter than a surfer's normal shortboard), mainly because of its flatter rocker, allowing the board to plane at a lower speed.
The short length of this board design creates a tight turning radius, making the board better suited to small surf although the above average surfer can also make them work in medium size surf as well.
Because of the added width, fish tend to ride flat on the wave and don’t transition from rail to rail very well making them difficult to surf vertically. However, the flat rocker and quick planning make this a very fast design that loves to race down the line and fly past slow sections on the wave. The fish is best for intermediate to advanced surfers.