Friends: 25 Lessons That Completely Changed Your Life

9. You're A Strong, Independent Woman Who Does Not Need To Smoke

Or in other words, make sure you're listening to the right advice. Every word of it.

8. Condoms Are Only 97% Effective

Not only was the seminal show a major part of your lifestyle choices, it also came with free scientific lessons. If you managed to pay enough attention to Ross' dino-speak, you could learn bits and pieces, and at various times throughout the show's run, we learned that chicks don't swim, how certain types of hair behave in high humidity and most shockingly for some, that condoms are only 97% effective. Best wear two then.

7. If You Get Stung By A Jellyfish... Pee On It

Another of those scientific revelations, and one that has definitely gone straight into the drawer in your brain marked Definitely Useful Information for when someone suffers a sting and you're within peeing distance. Sadly, it's not true. Back in 2007, The Scientific American actually warned that urine, on occasion, can actually cause the sting to burn more, rather than easing the pain. So put it away.