Sometimes, it’s hard to judge what should be considered “common knowledge.” Just when you start to assume that everyone knows that whales are not fish, for example, you meet an actual, human adult that is shocked to find out that they are, in fact, mammals.

Then, of course, there are the times when you’re the one who doesn’t know something. Obviously, that’s pretty embarrassing! The next 19 facts could fit into either category: you’ll either be shocked that it’s not common knowledge, or kicking yourself for not knowing it in the first place!

1. The blood in your body is not blue.


With or without oxygen, the blood in your body is red. It looks blue to us when we look at the veins in our arms because of the way that light reflects off our skin.

2. The Earth’s age has nothing to do with the Gregorian calendar.


The Earth is roughly 4.5 billion years old.

3. Goldfish shouldn’t really be kept in goldfish bowls.

3-not-so-common-knowledgePogrebnov Alexandroff/Wikimedia commons

Most goldfish bowls are far too small for goldfish. They’re naturally very large.

4. Frankenstein is the name of the doctor who created the monster. The monster in Mary Shelley’s novel is simply known as “The Monster.”
4-not-so-common-knowledgewikipediaBut if you really want to get annoying about it, if the Monster was created by Frankenstein, that would make The Monster Dr. Frankenstein’s son, so wouldn’t he also have the last name “Frankenstein”?

5. Ctrl/Cmd + Shift + T will restore an accidentally closed tab, and Ctrl/Cmd + Alt + Shift + T will restore accidentally closed windows.


This is a lifesaver, considering how many windows and tabs we all accidentally close on a daily basis!

6. The phrase is supposed to be “for all intents and purposes,” not “for all intensive purposes.”


What is an “intensive purpose?” You might as well say “for all intensive porpoises.” It’s just as meaningless.

7. The Netherlands and Holland are not the same thing.


The entire country is the Netherlands, but North Holland and South Holland are two separate regions of the nation. It’s like calling the U.S. “Carolina” or “Dakota.”

8. The police can intentionally give you a false sense of safety.


Technically, the police are under no obligation to tell you the truth. For example, if they say they have no intention of arresting you and only need a statement for their files, you can still be arrested if you say anything incriminating. Remember, you have the right to remain silent!

9. If you are impaled by something, don’t remove it from your body.


If an object is visibly sticking out of your body, just go straight to the hospital and let a doctor take care of it. The part that is embedded in your body might actually be keeping you alive by preventing you from bleeding out.

10. Nine months before Rosa Parks refused to move from her bus seat, Claudette Colvin did the same thing.


The NAACP did not want to use Colvin as the spokesperson for their civil rights campaign because she was 15 years old at the time and pregnant (by a married man). Rosa Parks was the secretary of the organization, so she was instructed to do the same thing. Talk about an unsung hero!

11. A pony is not a baby horse.


A baby horse is actually called a foal, while a pony is a horse of a particularly small breed.

12. Freedom of speech doesn’t protect you from other people’s reactions, criticisms, or other consequences.


In other words, the first amendment prevents the government from punishing you for what you say, but you still shouldn’t be a jerk.

13. Drowning in real life should not look like it does in television and movies.


When people are really drowning, instead of trying to call for help, their first priority should be trying to stay afloat.

14. Antiperspirant is not the same as deodorant.


Deodorant merely masks the odor, whereas antiperspirant actively helps prevent sweating.

15. You really shouldn’t feed bread to ducks.


Give them scraps of vegetables or birdseed instead. Bread doesn’t help them grow.

16. “Could’ve” is a contraction of “could have” and “should’ve” is a contraction of “should have.” The phrases “could of” and “should of” are completely incorrect.


 This is a real pet peeve of every editor. “Should of” and “could of” make no sense!

17. Antibiotics are not a cure-all.


Taking antibiotics contributes to antibiotic resistance, which could be a huge problem for the future of medicine.

18. You can tell which side of the car the gas tank is on by looking for the arrow; it’s on the gas gauge of most cars.


This should save you a lot of embarrassment the next time you rent a car!

19. Narwhals are 100% real.
19-not-so-common-knowledgewikipediaThey may look like sea unicorns, but they absolutely exist, and they’re pretty cool.

Hopefully these facts teach you something new. And if they didn’t, you can feel good with the knowledge that you already knew something that few others did. You smarty pants, you!

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