The world series baseball championship has been players since 1903 . there are 30 professional teams in the us and canada , they are divided into two leagues: the american league and national league . the champions from each league play each other in serie 26 times. this is more than any other team. no organization has named the world series as a “world championship “ event. however, sport fans still call it the “ world championship of baseball. what is this passage mainly about?