When you hear the name of a country you can immediately associate it with something, you hear England you think Big Ben, you hear Germany you think Beer and you can associate a lot of things to the USA. Food, landmarks, people but one of the biggest stereotypes is sports. American football and basketball are amongst the most popular ones.
Every year when spring comes around the NCAA's Division one has this tournament where the best of it's member colleges take part and play against each other. Because it's a single elimination tournament at the end you get the best college team in the United States. This might not sound like much at first but it's an extremely important part of American culture. At one point in time college sports, basketball especially was considered to be more pure than professional sports and many fans believed that the professional teams are just in for the money and that college basketball remains true to the game. This is how college basketball became so popular and why people each year fill out brackets and probably will be filling out a 2012 NCAA Tournament bracket as well.
Just to show you how much of an impact this tournament has on American society, after people get the 2012 NCAA Tournament Schedule it is estimated, because it happens each year or at least that's the myth that business each year lose 1.7 billion dollars or more because of March Madness and the productivity drop that results from it. There are many reasons why this is just a myth and not correct but this isn't the place to talk about that. The point is college basketball remains and becomes more popular with each passing year and it was and remains a very important part of American culture.