The entire show centers around relationships. Whether it be the friendship of Jerry, George, Kramer and Elaine or the relationship they had with others. Mr. and Mrs. Seinfeld, The Costanzas, Uncle Leo, Newman, Mr. Peterman, Susan Ross, David Putty, George Steinbrenner (voiced by Larry David) and the countless other relationships they had with the opposite sex. There was ALWAYS a good story to tell. It could've been Jerry and George talking about the ridiculous reasons why they continuously break up with a different girl every week, Elaine and Putty breaking up at the drop of a hat, only to get back together again later on. Or the time Kramer and Newman tried to earn a few extra bucks by hoarding empty soda cans in a mail truck, in an attempt to talk them to Michigan and sell them for a profit. I don't think I need to tell you that they were of course unsuccessful in that venture. The stories really are endless, and the supporting cast of characters play their parts perfectly in order to keep the stories fresh and funny.