Evolving from older bat-and-ball games, an early form of baseball was being played in England by the mid-eighteenth century. This game and the related rounders were brought by British and Irish immigrants to North America, where the modern version of baseball developed. By the late nineteenth century, baseball was widely recognized as the national sport of the United States. Baseball on the professional, amateur, and youth levels is now popular in North America, parts of Central and South America and the Caribbean, and parts of East Asia. The game is sometimes referred to as hardball, in contrast to the derivative game of softball.
In North America, professional Major League Baseball (MLB) teams are divided into the National League (NL) and American League (AL). Each league has three divisions: East, West, and Central. Every year, the champion of Major League Baseball is determined by playoffs that culminate in the World Series. Four teams make the playoffs from each league: the three regular season division winners, plus one wild card team. Baseball is the leading team sport in both Japan and Cuba, and the top level of play is similarly split between two leagues: Japan's Central League and Pacific League; Cuba's West League and East League. In the National and Central leagues, the pitcher is required to bat, per the traditional rules. In the American, Pacific, and both Cuban leagues, there is a tenth player, a designated hitter, who bats for the pitcher. Each top-level team has a farm system of one or more minor league teams. These teams allow younger players to develop as they gain on-field experience against opponents with similar levels of skill.