Your average American generally has a good idea of what is entailed with a basketball, football, or baseball game. Additionally, they could probably tell you a thing or two about soccer, hockey, and golf, as well. But if you look outside the swimming community, not many people are as familiar with the sport of water polo.
Contrary to the name, water polo is vastly different from the sport of polo. Polo is a game played on horses, wherein the riders try to whack a ball with a long-handled mallet into the opposing team's goal. Now, the "putting a ball into a goal" aspect is actually the same for the two sports, but this is where the similarities end.
Water polo is a team sport played in a pool. Each team consists of one goalie and six field players. The game is divided into four quarters and is a transition sport, meaning that the teams have to adjust from offense to defense with every possession. In the transition regard, water polo isn't really all that un-similar to sports like basketball or soccer. After a goal is scored (this is achieved by someone shooting the ball into the net, without it being stopped by the other team’s goalie), the teams line up at mid-pool and the non-scoring team receives possession, much like in soccer.
The uniforms for water polo are fairly basic. Teams will typically wear matching swim suits, usually "Speedo"-style, and caps. The caps have numbers on the sides, enabling the officials and scoring table to identify the players. The numbers also help the coaches identify their players, too. Goggles are not usually worn, unless a player needs prescription lenses so as to see. Mouth guards are strongly encouraged, but not necessarily mandatory, for children who have braces.
Two referees walk lengthwise along the pool, on opposite sides, to officiate the action. When a foul occurs, the ref who is making the call will give a hand signal, so that the players and coaches know what call was made. Coaches are not allowed to talk to the referees during the game and may receive yellow (warning) or red (ejection) cards for doing so.
Water polo is a growing sport in America. It is rather popular with swimmers, but non-swimmers can be found taking part in the action, too. Basketball players, for example, can make for exceptional water polo players, on account of understanding concepts such as offense and defense.
This is merely an introduction to the sport of water polo. There are many further components to the game, but hopefully this provides some insight into the sport. At the very least, it should at least clear up one common misconception… Horses are not used in water polo!