Seinfeld stood out from the many family and group sitcoms of its time. None of the principal Seinfeld characters were related by blood or type but remained close friends throughout the seasons. The episodes of most sitcoms like Family Ties, Who's the Boss? and Full House revolve around a central theme or contrived comic situations, whereas many episodes of Seinfeld focused on minutiae, such as waiting in line at the movies, going out for dinner, buying a suit and, basically, dealing with the petty injustices of life. The view presented in Seinfeld is arguably consistent with the philosophy of nihilism, the idea that life is pointless.

Source: Wikipedia.org