The Simpsons isn't just the longest-running scripted primetime show in US TV history, it's also one of mankind's greatest achievements. Or at least it was until around the late '90s when its quality took a well-documented nosedive.
Nevertheless, with more than 600 episode and almost 30 seasons under its belt, the series following America's finest yellow-skinned family's longevity is unquestionable and no amount of dud episodes will ever dilute the sheer quality of their first 10 series.
During its golden age, The Simpsons' jokes, cultural references, visual gags and quotable lines became embedded in the collective consciousness and are never unfunny no matter how many times you hear them. This is the beauty of the show and, along with its heart, is the reason it has stood the test of time.
But it wasn't all about obvious gags that smacked you in the face: the other big selling point of the show was always its commitment to hiding little details that took some effort to really notice.
The writers who worked on the series back then are some of the most talented people in the television industry and they're masters of subtly, as proven by the amount of hidden jokes they've shrewdly sneaked under the radar over the years.