The world of sports is active, dynamic, and exciting. Sports, especially team sports, have gained millions of fans worldwide. Team sports like American football, soccer, basketball, baseball, hockey, and rugby have great numbers of fans and watchers. These sports also have national and international competitions, and this gives the sports enthusiasts the chance to express their admiration and cheer for their preferred team.

Sports fans usually purchase or obtain memorabilia, such as balls, bats, mitts, caps, shirts, hockey pucks, hockey sticks and other items signed or even previously owned by famous players. Some fans may lie low and just purchase shirts or other pieces of clothing, accessories or objects that are similar to the ones used by the sports teams and players.

Shirts, jackets, bags and other apparel have been used to promote the different sports teams. An example is the sport shirts displaying the flags of the countries where the different soccer teams come from. The fans buy the shirts with the flag of the country they are rooting for. Another example is the basketball jerseys of the different teams. An enthusiast usually purchases the jersey that has the name and number of his favorite player.

Other sports-inspired shirt designs may not necessarily promote a specific team or player. They may just resemble the general appearance of a piece of clothing used in a certain sport. An example is the large sweater used by hockey players. Some hockey enthusiasts may not necessarily favor a team, but just love the sport itself. They may buy clothes designed to look like the hockey sweaters. Another shirt design inspired by sports is the referee top.  

A referee top, as its name says, looks like the typical shirt worn by a sports referee; it has vertical black-and-white stripes and may be collared or v-necked. Many referee shirts sold today deviate from the typical t-shirt worn by actual referees. There are many variations that are manufactured.

Even if most sports officials and referees are male, referee shirts for ladies are also popular. Some of them have the aforementioned variations. A referee shirt for a girl can have different neckline shapes such as round, v-neck, deep v-neck, and more. Referee shirts even come in sleeveless variants. The most characteristic feature of referee shirts is the vertical black-and-white stripes.