Soccer is a sport played between two teams of eleven players with a spherical ball. The game is played on a rectangular field with a goal at each end. The object of the game is to score by getting the ball into the opposing goal. The goalkeepers are the only players allowed to touch the ball with their hands or arms while it is in play and then only in their penalty area. Outfield players mostly use their feet to strike or pass the ball, but may use their head or torso to strike the ball instead. The team that scores the most goals by the end of the match wins. If the score is level at the end of the game, either a draw is declared or the game goes into extra time and/or a penalty shootout depending on the format of the competition. In soccer games governed by the National Collegiate Athletic Association (NCAA), between three and six identical balls must be furnished by the home team at the beginning of the game or the game cannot begin.  Specifications are set for the ball’s circumference, weight and pressure at the beginning of the game; however, the ball is allowed to increase in weight, within an approved range, should it get wet during play.

Women’s lacrosse is a sport played with twelve players on each team. The object of the game is to use a long-handled lacrosse stick to catch, carry, and pass a solid rubber ball in an effort to score by ultimately hurling the ball into an opponent’s goal. Defensively the object is to keep the opposing team from scoring and to dispossess them of the ball through the use of stick checking and body positioning. Equipment required to play is different from the men’s. Women are only required to wear eyewear/lacrosse goggles, and a mouth guard. Their stick has restrictions too, it has to be a certain length and the pocket cannot be too deep but the lacrosse ball sizes are the same. Colors appear to be tightly controlled in NCAA Women’s Lacrosse.  Starting in 2008, gray was added to the list of colors approved for the goalie’s uniform bottom.  Previously, the bottom portion of the uniform had to be either the team’s predominant color or black.  While it is not new in 2008, the color of the ball must be solid yellow.

The Rugby Football League (RFL) sets rules by age division for players in England. Full 13-A-Side rules are used from the age of 12 onwards.

The size and shape of the ball used at the high school level is the same as that used at the Olympic level. As defined by the National Federation of State High School Associations (NHFS), the ball must be leather or plastic.

USA Field Hockey is the national governing body for the olympic-level sport of field hockey, both indoor and outdoor, in the United States. The Rules of Hockey at the Olympic level are issued through The Hockey Rules Board of the International Hockey Federation (FIH).

All you have to do is drop a field hockey ball on your foot to think that it weighs five pounds rather than five ounces. USA Field Hockey is the national governing body for the sport of field hockey in the United States and is a member of the United States Olympic Committee (USOC). The Rules of Hockey at the Olympic level are issued through The Hockey Rules Board of the International Hockey Federation (FIH).

Similar to the game of billiards, the game is played using a cue and 22 snooker balls: one white cue ball, 15 red balls worth one point each, and six balls of different color: yellow (2 points), green (3), brown (4), blue (5), pink (6) and black (7). The red balls are initially placed in a triangular formation, and the other colored balls on marked positions on the table known as “spots”. Players execute shots by striking the cue ball with the cue, causing the cue ball to hit a red or colored ball. Points are scored by potting the red and colored balls (that is, knocking them into the pockets) in the correct sequence. A player receives additional points if the opponent commits a foul. A player wins a game of snooker by scoring more points than the opponent. A player wins a match when a predetermined number of frames have been won.

The Federation Internationale de Natation (FINA) regulates Olympic water polo for both men and women. They keep things simple, by specifying only the most basic characteristics for the ball – it must be round and waterproof, without straps or greasy coverings. With women able compete in the Olympics beginning in 2000, a slightly smaller ball was introduced into the games.

The 2007/2008 Official Beach Volleyball Rules determined by the Federation Internationale de Volleyball (FIVB) dictate that the balls be spherical, flexible and uniform within a match. At 66 to 68 cm in circumference and appearing in bright colors, the balls are made of materials that do not absorb humidity.

The National Federation of State High School Associations (NFHS) has a committee that writes the rules for many high school matches.  The physical specifications of an NFHS ball are very similar to those of an NCAA ball, with the circumference being the only difference.  While any NCAA ball could be used in a NFHS game (if the NFHS authentication markings appear), the reverse may not be true, depending on the actual circumference of the ball.