The fastball is the most common type of pitch thrown by pitchers in baseball. Some "power pitchers," such as Nolan Ryan and Roger Clemens, have thrown fastballs at speeds of 95–106 mph (152.9–170.59 km/h) (officially) and up to 108.1 mph (174 km/h) (unofficially), relying purely on speed to prevent the ball from being hit. Others throw more slowly but put movement on the ball or throw it on the outside of the plate where the batter cannot easily reach it. The appearance of a faster pitch to the batter can sometimes be achieved by minimizing the batter's vision of the ball before its release. The result is known as an "exploding fastball": a pitch that seems to arrive at the plate quickly despite its low velocity. Fastballs are usually thrown with backspin, so that the Magnus effect creates an upward force on the ball, causing it to fall less rapidly than might be expected. A pitch on which this effect is most marked is often called a "rising fastball." Although it is impossible for a human to throw the pitch fast enough with enough backspin for the ball to actually rise, it does create the illusion of a riser to the batter due to the unexpected lack of natural drop on the pitch. Colloquially, use of the fastball is called 'throwing heat' or 'putting steam on it', among many other variants.