Fifty years ago, a half-hour sitcom first appeared on CBS. “The Mary Tyler Moore Show” starred its namesake actress as a new kind of TV woman: professional, unmarried, independent. And very, very funny. This special edition of LIFE delves into the seven-season Emmy-winning mega hit, including its beloved cast of quirky characters, the top-10 episodes, special guests and several spin-off series, that changed television in powerful and lasting ways and painted a new picture of the American working woman.