Sitcoms have been a television staple for almost as long as there have been television sets in most homes. Everyone likes a laugh or two, and these sitcoms have been a reliable and popular source of humor. Great writing together with stellar casting made these shows television magic. Essentially, the cast is much of what brings us back to a sitcom again and again. Be it their mishaps, adventures, or one-liners, the right cast takes viewers into a fictional world with characters so authentic, you might just forget they aren't real.
However, over the seasons, a lot of the cast end up changing, whether physically or by being replaced by different actors. So to see how the cast of some of the most popular sitcoms have changed, check out this gallery.