How could we forget about Mark? This is actually the character who changed everything in the series forever when Rachel gets her first job that she really likes at Bloomingdale’s. Of course, he’s the main reason behind Ross and Rachel’s first breakup, because of how jealous Ross gets when he’s around. But that’s not the last game changer he introduces into the series. In the least season, he comes back and actually offers Rachel a new job in Paris... And the rest is history! Eckholdt has worked on other series and films, but Mark remains his most popular TV character.