Basketball as a sport actually began in college, so college basketball was the very first way that the game, that has since become the most popular in the USA was ever played. At the YMCA International Training School in Springfield Massachusetts, nowadays known as Springfield College, physical education teacher James Naismith was tasked with coming up with a game to keep track athletes in shape over the winter of 1891 without risking their being injured. The non-contact game that he devised to fulfil this task was basketball. The first recorded game of the sport took place that December and college basketball, and basketball, was born
The sport gradually became popular within the college environment over the years with inter-college competition beginning to take place by the beginning of the 20th century. It was the subsequent movement of the game onto the inner-city streets however which really propelled it into the national consciousness and let to it eventually becoming the biggest of the big four US sports with nationwide professional leagues, along with American Football, Baseball and Ice Hockey.
Over the years, basketball has maintained its ties to the college leagues which gave birth to the sport. The yearly draft of young players into the professional NBA comes from the top talent from the college leagues. The relationship between the NBA and college basketball is mutually beneficial. College teams are able to keep players that would otherwise turn professional earlier, which maintains the standard of play and makes it profitable for the colleges. The NBA has a fertile breeding ground for young talent to come through without having to fund a commercially unviable minor league. College basketball is very popular and there are certain areas of the US where the college teams are more popular than NBA basketball.
The relationship between the professional NBA and college basketball is not however without any controversy. Accusations have been made that college basketball is exploitative. Academically undeveloped players are recruited purely on the basis of their sporting ability. Because of the pressure on coaches and colleges for the sports teams to do well, these college players often receive very little in the way of education during their time playing for the college team, with the focus on them training. As a result the players eventually leave the college system without either having been paid or with an education. In the case of those who do not subsequently make it as professionals in the NBA, these players can be said to have nothing to show for the years they have given the college team, which the college has profited from.