The Simpsons

Currently in its 25th (wow!) season, 'The Simpsons' is the the longest-running American sitcom and the longest-running American animated program of all time. Created by Matt Groening, it started life as a sketch on the 'Tracy Ullman Show', before finding its place on prime time television. A cultural phenomenon all over the world, you're probably hard pressed to find a person who can’t identify Bart, Homer or even baby Maggie. After 25 years on air and over 500 episodes, remarkably audiences haven't tired yet of watching the exploits of this ever youthful small town family.

American DadAmerican Dad

American Dad

'The Simpsons' isn't the only cartoon that’s enjoying a lengthly run. Seth MacFarlane’s ‘American Dad’ is currently in its tenth season and the sitcom will continue despite being dropped by Fox, moving to TBS  in July 2014 for its 11th run. Of course an 11th season for' American Dad' puts it hot on the heels of its Seth McFarlance predecessor, 'Family Guy' which has so far racked up 12 seasons.

ER

The show that gave us George Clooney also gave us 15 seasons and over 300 episodes, making it longest-running primetime medical drama in American television history. It was also the recipient of many accolades during its 15 year run including 24 Emmy nominations, making it also the most nominated drama program in history. If that wasn't enough it also launched the career of George Clooney, though we might have already mentioned that.

Grey's Anatomy

Another medical drama that’s kept us all enthralled is ‘Grey’s Anatomy’. Since 2005 we’ve been watching the drama unfold in what is now the Grey-Sloane memorial hospital. Sure this one might feature one of the most unlikable lead characters ever, (sorry Meredith), but after 10 seasons it's still pretty gripping stuff. However the show is facing a pretty uncertain future as of late as its current season will be the last to feature main cast member Sandra Oh.

Married with Children

It may look incredibly dated now but back in the late 80s and early 90s the Bundy family were a big deal. This sitcom was Fox’s first prime time series and enjoyed an 11 season run between 1987 and 1997. The Bundy’s might just be televisions most dysfunctional family of all time, but aside from that the show is also very well remembered, thanks in no small part to the Frank Sinatra theme song.

Smallville

Telling the story of the young Clark Kent before he became Superman, this show was pitched with the rule ‘no tights no fights’ and audiences quickly responded positively. The show began in 2001, long before Superhero origin stories were the done thing and ran for 10 seasons before ending in 2011. Its decade long run on tv means it is the longest running science fiction television series ever in North America.

Two and a half menWith or without Charlie, 'Two and A Half Men'

Two and a Half Men

Wether it's Charlie Sheen or Aston Kutcher, it doesn't matter, audiences are still enjoying ‘Two and a Half Men’. This show started in 2003 with Sheen as playboy Charlie Harper. Then a lot of off screen drama ensued and poor Charlie met an untimely death. Moving in to replace him came Walden Schmid played by Ashton Kutcher. Now without Sheen the show is still going strong and into its 11th season, proving that loosing a main cast member doesn't necessarily have to mean a sitcom’s end.

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