Did you know that when a pufferfish “puffs up,” they are filling themselves with water, not air? If you did, congratulations, you have more common sense than most, as this is not as widely known as one might think. But then again, there is so much information out there that it’s entirely possible to be unaware of “regular” things for years.

Someone asked “What is a fact that you only recently learned, but should have known for ages?” and netizens shared their best examples. So get comfortable as you scroll through, upvote your favorites and be sure to comment your own stories below.

#1

There are people who do not have an internal monologue. I was like WTF.

Image credits: pantherghast

#2

Puffer fish fill up with water to inflate. Not air. I don’t know where I thought the fish got the air from.

Image credits: Bad_Elephant

#3

Babies aren’t supposed to drink water apparently. Not that I should have known, but never would have guessed.

Image credits: GiuseppeJ03

#4

Cooking food in a cast-iron skillet increases the iron content in your meal. I don’t know why I never thought of it like that until recently…

Image credits: hay9

#5

In Super Mario Brothers on the NES, you can continue where you lost your last life by pressing a+start on the main screen.

Image credits: Dainiad

#6

That the filter in the dishwasher should be cleaned out monthly. Not my original schedule which was never.

Image credits: sufferpuppet

#7

Octopus predate dinosaurs.

Image credits: FluffyTid

#8

Human skin doesn’t have the ability to sense water. We can only tell that something is wet because of temperature or pressure, but we don’t have the proper receptors for water itself.

That’s why sensory deprivation tanks with room temperature or barely warm water work so well, and why you can’t tell if clothing left out to dry is damp or if it’s just cold.

When I read that somewhere, it was a huge mindf**k. Now I think about it constantly.

Edit: We know that humans don’t have these receptors because we know that certain animals DO. Including fruit flies and cockroaches. Which is weird.

Edit: To all the people saying that they test an object’s wetness by placing it against their lips or cheek, this is still exactly the same principle I’m describing above. You can’t feel the wetness, you’re feeling the sensation of air moving against the wetness. It’s no different from holding the object in your hand. We rely on cues like temperature and pressure to decide if something is wet.

Edit: A lot of people are saying this is b******t and I made it up because you CAN tell when something is wet. Congrats, you’re restating exactly what I already said. We rely on environmental cues to determine it. Also, what I’m referring to is hygrosensation. Do your own research. Google it.

Image credits: eli-the-egg

#9

Oxen are just employed cows, not a whole separate species of bovine.

Image credits: InfernalOrgasm

#10

Until yesterday I thought blackened chicken was just that, chicken that had been grilled the f**k out of.

Turns out it’s a delicious blend of spices.

Image credits: Turbulent_Juicebox

#11

If you write on a dry erase board with a permanent marker, you can remove it by writing over it with a dry erase marker and then erasing.

Image credits: reddittheguy

#12

I knew that a litter of kittens can have different fathers but I just found out that twin humans can have different fathers also. Crazy.

Image credits: Wonderful_Whereas402

#13

Up til she was about 25 my ex wife thought reindeer were made up for Christmas movies.

Image credits: i_just_say_hwat

#14

Groundhogs and woodchucks are the same animal.

Image credits: jamesiscoolbeans

#15

The potato company OreIda is a named after two states that produce much of their potatoes, Oregon and Idaho.

Image credits: Swimmingllama

#16

Abcdefg has the same melody as twinkle twinkle little star.

Image credits: FaveDave85

#17

Ponies are not baby horses. They are small foreveeeeer

Image credits: bearclawmcgee2

#18

Pickles are just small pickled cucumbers…. what? Who knew? Apparently everyone.

Image credits: Dougsbar

#19

A litre of water weighs a kilogram.

Image credits: anon

#20

Maybe not recently learned but a few years ago when I found out how our solar system is just bumping along through space really fast, I can’t believe I didn’t know that. Thought we were stationary. Big ole dumb.

Image credits: softstones

#21

Eartha Kitt, the woman who sings Santa Baby, also voiced Yzma from Emperor’s New Groove.

Image credits: Mr_Archer1216

#22

The Holy Roman Empire only ceased in the 19th century because of napoleon. For some reason I always think of the early 12 century.

For some reason it’s hard to fathom Rome only ceased to exist in a bastardised form 300 years ago.

Image credits: Johnwayne18889

#23

After decades of doing it wrong, I realized from NASA’s website that the abbreviation for US time zones during Daylight Saving Time is EDT, CDT, MDT, PDT… That is, Daylight Time. EST, CST, MST and PST are for standard time, which is what we just went back onto a week ago.

Image credits: monkeyselbo

#24

Revolving restaurants on towers only revolve on the inside. The entire top of the structure does not move. That would be insane.

Image credits: CurNoSeoul

#25

To be tea, it has to come from the tea plant. Black, white, green, oolong teas are all the same plant but with different processing and harvesting.

Anything else that calls themselves a tea is actually a tisane – including roiboos.

Image credits: Mysterious_Lesions

#26

White wine does not come from green grapes.

(Excuse me, but does it not stand to reason, f’r Crissakes?).

Image credits: druu222

#27

Linen is not just a particular weave of cotton. It’s made from a completely different plant (flax).

Image credits: estreya2002

#28

When using nasal spray, you are supposed to **inhale** and spray simultaneously. I discovered this while watching TV a few weeks ago.

Nobody ever showed me how to fkn use a nasal spray, and it wouldn’t have occurred to me to do it on my own because it feels a bit uncomfortable, but my allergy sprays work sooooooo much better now.

I feel like a dumba*s.

Image credits: snappyirides

#29

Margarine is made from oil not butter.

Image credits: tnmoltisanti420

#30

Percentages are always reversible.Example 32% of 78 is same as 78% of 32.

Image credits: Jedihallows

#31

How the Spanish arrived in the Philippines to conquer and settle. They did not sail East from Spain, you you would think. They sailed West from their Mexican colony across the Pacific.

#32

When they kept liquor stores open at the beginning of the pandemic, it was to ensure that alcoholics wouldn’t overflow the hospitals even more by suffering from alcohol withdrawals.

#33

My father is not my biological father, which has tainted my medical history my entire life and I had to go searching for my biological father after my cancer diagnosis.

I love my father, and don’t blame my parents, but that’s some s**t I should have known.

#34

It wasn’t new information, but through the footage during severe storms from massive waves crashing on ships today, realizing how terrifying it would be to cross the ocean in the 1400s.

#35

How common stillbirths are.

#36

Another one I only learned about 2 years ago. There are people who are “mind-blind” and can’t visualise objects or images in their mind. It’s called Aphantasia and I (and about 3% of the population) have it. Never know other people could mentally visualise their thoughts.

**edit: Thanks for the many upvotes and replies.** Seems like this is quite interresting to many people who have it or don’t understand it. I wanted to add some information that came to me during some conversations here:

1) It seems to happen in different “degrees” on a visual spectrum. Some people are also face-blind, some can visualize very simple forms like square for example. Someone here said that it’s maybe like with different image qualities. Some can see images in 4K HD, some have blurry edges on their images, some see only very simple shapes, some can’t image anything visual.

2) I can clearly explain to you what my house looks like, I can describe every part of my house from memory, I could draw it to you, but maybe I would get the textures a bit wrong but everything that is there every day, I can describe it. for example, the couch I sit in every day is something I could draw and know if I touch it that it’s my couch, but I might get the color wrong or the texture. The older a memory, the more faded it is.

3) I don’t have many memories from my childhood. It’s very vague. Like not even a picture of the moment. But a blurry picture where I can’t focus, I might see a face or a house that I saw many many times, or a really huge event for me as a child (like dancing in front of the whole school at a talent show) I remember the event, some details, (like the cool sunglasses I was wearing with led lights in it) but everything around it is one vague blur, no further details about the stage, theater, audience, I only remember the applaus very well 😉

4) something else clicked: I’m a real story teller and i’m kind of a “funny guy” so people like to listen when I talk/tell stories. But I had different occassions where I’m telling something that I recall happened to me (altough maybe I would spice it up for humorous effect) , but then afterwards I had people coming up to me to say that they told ME that story and it happened to them and I guess I create a false memory as it was my own. (and felt really bad about it)

*** edit 2:
5) apparently you people SEE numbers when doing calculus?! Now I understand why my partner thinks it’s odd that I “still” count with my fingers or try to write in the air. That’s all I got to work with!

*Questions I still have. People who don’t have this. Can you really taste a taste when thinking about it, and smell a smell?*.

#37

Bryers was the best ice cream years ago. Now it’s garbage. Take look at the containers. They are now frozen desert. Bryers no longer legally meets ingredients of ice cream. Sad where it is now.

#38

That the “Spanish flu” probably started in Kansas soldier barracks and spread due to WW1. The only reason it’s named the Spanish flu is because Spain was the only country that reported on it- many other countries had a media blackout on it.

#39

Sigh, to remove the top from deodorant, you need to twist it up. I was pulling the plastic barrier out with my teeth.

I know.

#40

My cat used to never drink a lot of water and she would just spend a lot of time staring at the bowl, turns out she was experiencing whisker fatigue so I got her a wider bowl.

Poor cat.

#41

There’s a wee triangle next to the petrol light which indicates which side of the car the fill cap is on.

Just realized this about my car yesterday and I think it applies to all cars.

I’ve been driving for two decades.

#42

Narwals are real.

#43

You are only supposed to have a few crackers with your soup.

So growing up my parents were not fond of having me. So by age 5 i didn’t eat unless i made my own food. So when i got to the point where i could make soup i would eat a whole sleeve of crackers for every bowl i ate. I didn’t find out until just recently how unhealthy it was. I always ate soup when i was alone since its single serving. The few times i got it at a restaurant i assumed they wanted you to pay more to get the rest of the crackers so they tease you with 2 packs.

Edit: Wow, thank you for all the amazing responses. For context my parents always had food around, i was never without anything. But my parents basically ignored me whenever they were not emotionally abusing me. I couldn’t tell you why, but i was often told i was a mistake. They both passed during the pandemic but i was able to build a relationship with my dad a bit before they passed. I have 2 boys of my own now and of course i am over compensating by showering them with love!

#44

That Sherbert doesn’t have two R’s in it and is Sherbet! Who the hell says Sher Bet!? I’m in my late thirties and just found this out in 2023.

#45

I guess this only applies for my context. But I (30 yo) only quite recently learnt my neighbouring country (Malaysia) is in Borneo as well. I’ve always thought Malaysia was only the mainland part.

#46

Correct way to do a rolling start in a manual car when the battery is dead.

Put the transmission in Neutral gear.

– Instruct the person outside to push the car forward to gain some momentum and keep pushing until the vehicle reaches a speed of about 5-10 mph.

– Disengage the clutch and shift into second gear and quickly engage–or “pop”–the clutch

Don’t Try This With an Automatic , not possible and will damage stuff.

#47

If your tee shirt has a tag at the bottom, it’s always on the left (at least if you’re a guy, not sure if this is one of the things that’s mirrored for the ladies).

So many wasted seconds figuring it out.

#48

English is a Germanic language not Latin.

#49

Soaking dishes in the sink overnight actually works. My parents wouldn’t go to bed if there was a dirty dish. That’s how I was raised. If it was stuck that meant work harder.

Recently my wife and mother in law let something terribly cooked on soak overnight and I’ll be damned if worked.

I honestly thought “letting it soak” was code word for “lazy a*s.” Or used as a trope in media to represent someone that shirked work or was too good/too lazy to do dishes.

#50

Gunna get buried here but I thought expatriates was only referring to Americans living abroad and was spelled like ex-patriots. I thought it was really odd but never questioned it. However it seemed odd enough to me to also never bring it up so I am learning.

#51

Pineapples do not grow on trees. I was barely in my 40s.

#52

Being born and raised in Florida, I only recently learned we have native crocodiles.

#53

For 42 years of my life I thought that historical people who killed themselves by sticking their heads in the oven (ie Sylvia Plath) were just _metal as f**k_ and baked their brains to death, and only just learned that old timey ovens ran on highly toxic coal gas that basically knocked you out permanently.

#54

On Duck Hunt on the NES if you have a p2 controller you can direct the ducks.

#55

I always knew that Alaska wasn’t like, an island the way an inset on a map of the US depicts it, but I never realized just how gigantic and how far away from the ~~mainland~~ contiguous United States it actually is. Same goes for Hawaii—never realized how far southwest it is from us. I’m in my mid-30s, reasonably intelligent, and I noticed this stuff when looking at a world map like sometime last year. Embarrassing.

#56

That the von Trapp Family Singers were real people and The Sound of Music was based on a true story.

#57

I didn’t know lamb was a baby sheep until very recently. I was reading a farm book to my 3 year old kid and I was enlightened… I cried. No wonder the lamb chops are so small. I should have known! I know.

#58

It took me WAY TOO DAMN long to realize that it’s called deodorant because it de-ODOR-izes you! I think I was 29 when I figured this out. I am 30.

#59

It’s not the stripper that spins- it’s the pole. Blew my mind, I thought those ladies were masters of centrifugal force AND core strength!

#60

That if you boil eggs in salted water, the peels come off easier. Plunge them in cold water for an even better effect.

#61

When you have your face in the flow of the shower you can just open your mouth and breathe, you don’t need to hold your breath and take your face out of the shower flow when you need to breathe, as I was doing for most of my life. It seems even more stupid now that I’ve written it down, but I genuinely just realised this a couple of years ago, I’m 37…

#62

Space heaters are called that because they are used to heat up a space. Not because they use space age technology.

#63

When you say no because you don’t feel comfortable doing it and someone pushes you to do it anyway, just don’t do it. I just learned about boundaries and I’m freakin’ over age 50.

#64

It is the “Cupid Shuffle,” not the “Cuban Shuffle.” Source, went to a wedding Saturday, thought I misheard the name, looked it up and found I’d been mishearing it for years.

#65

How to put air into a tire.

#66

The Aztecs had only been in that area for about a century before the Spanish arrived, were just as obsessed with conquering the local people, and likely were just as bad as the Spanish to those people.

In addition to ruinous taxes and tributes, the Aztecs demanded their vassal states supply them with people for their rituals that sacrificed tens of thousands of people per year. Some of these sacrifice rituals specifically called for children or pregnant women.

I always thought the native peoples of the Americas were pretty innocent victims of imperialism and colonization, but the Aztecs lost to just a few Spaniards because the other peoples of the area joined the Spanish against them.

I don’t know what’s worse, to be enslaved in a silver mine or to lose your life or your kid’s life to human sacrifice.

#67

If you type something wrong on an iPhone calculator but only want to get rid of the most recent digit you typed, you just swipe.

#68

That opossums are great for the environment and if your dog attacks them, you should stop them. And if you’re brave enough to move them to safer grounds, they will emit a foul odor while playing dead. It stinks, but if you’re willing, pick them up like a kitten (scruff of neck)and relocate. Don’t worry, like skunks, the smell comes from there a**s, but! they don’t douse you with the smell. It’s just to deter predators.

#69

Diagon Alley is diagonally. Realized this like 20 years after watching the first Harry Potter movie.

#70

Ok, I feel dumb but in my defense I’m not a wine drinker. I had no clue wine types are named after the grape variety that was used to make it.

#71

Parkways used to be roads that … ended in a park.

#72

When you snap your fingers, the sound is from your finger hitting your palm.

#73

It is prerogative, not perogative.

#74

Talking doesn’t scare the fish, grandpa just wanted us to shut up.

#75

That asbestos is found in nature. I just thought it was some awful human invention used for insulation.