Softball is based on the game of baseball and was originally designed as an indoor version of the sport. Its invention was a fluke, as described by SoftballPerformance.com, the result of a playful toss of a boxing glove by a Yale alumnus at a Harvard graduate. The Harvard man swung a stick he was holding and knocked the glove away. While each sports ball is significantly different, the two share a common history.
No matter what level, be it youth or professional adult leagues, the weight and circumference of a baseball is the same. Little League Baseball, the National Federation of High School Associations, National Collegiate Athletic Association and Major League Baseball each stipulate that the ball must weigh between 5 and 5 1/4 oz. and have a circumference between 9 and 9 1/4 inches.
Baseball Material and Color
The official ball of Major League Baseball, as well as those used by the Little League, high school and college ranks, is white. Major League Baseball's rules go into more specific detail. The rules state that the ball must be spherical and made with yarn wound around a core made of cork, rubber of a similar material. Two strips of horsehide or cowhide cover the ball and are stitched together.
Each level of play certifies balls for use. Those used in Little League will carry the phrase "Little League Baseball" on the side, while balls used at the Major League level will carry the league's logo and signature of the sitting commissioner of baseball.
The primary difference between a baseball and softball is size. The NCAA's 2010-11 rule book states that the official softball for use should be between 11 7/8 and 12 1/4 inches in circumference, with a weight between 6 1/2 to 7 oz. The NFHS and most youth leagues have adopted this rule. Little League Softball lowers their standards to 11 7/8 to 12 1/8 inches, with a weight between 6 1/4 to 7 oz.
Softball Color and Material
As opposed to the white leather and red stitches found on a baseball, softballs can come in multiple shapes and colors. The Amateur Softball Association of America, NCAA and NFHS each differ on the appearance of the ball. The ASA, which is the sport's governing body in the United States, only allows its certified balls to be used in sanctioning tournaments, and that ball must be either white or optic yellow. The NFHS requires its own series of certified balls in the same colors as ASA, while the NCAA permits only yellow balls. What the trio of organizations can agree on is the ball's construction. According to the NCAA, this includes a polyurethane, long fiber kapok or cork and rubber core, covered by chrome tanned horse or cowhide.
Coefficient of Restitution
Softballs got their name because their core is softer than a baseball and, therefore, they do not spring off the bat in the same way. The coefficient of restitution is the measure of this springboard effect, with a higher number translating to a greater launch when ball meets bat. An NCAA baseball's coefficient cannot be greater than .555, while a softball may not exceed .470.