It happens to all of us. You're with your friends, and suddenly someone makes a reference that everyone else seems to get — and you're not in on the joke. Why? Because as well-versed as you may be in Friends trivia or Game of Thrones theories, you might have a big ol' blind spot when it comes to classic movies. Whups.

No biggie, though. That's easy enough to deal with, even if you never go back and audit a Film 101 class. All you've got to do is sub out some of the binge time you've been dedicating to the television section of your Netflix queue and instead tune in to some of the most influential movies of the 20th century. Which ones should you be watching? In no particular order, we've picked out 30 of our favourites — and we'll be adding new titles each month. All you've got to do is bring the popcorn.