Sitcoms come and go. Some last for years while others are literally cancelled after one airing. The key to a successful show goes beyond good writing. You need actors who take the craft to another level. Their ability to get into the character and make it believable – no matter the zany situations they face – allow them to stand the test of time. With that in mind, here’s a look at 8 sitcom characters that rank among the greatest in history.