You were "today years old" when you learned....what?
You learn something new every day, even if you don't think you do--but when you're aware that you learned something that you really should have known, boy, you are really aware.
At the same time, you're like...how did nobody ever tell me this? Was I supposed to divine this from thin air on my own?
u/Lawvamat asked:
What did you just recently learn that "everybody knows"?
Here were some of those answers.
Hoodwinked
I went to Venice with my school and a group of girls told me that they eat their tampons after they are done with them. It was for some stupid reason like to regain their iron or something. I believed it and even the teachers played alone. I went back home to the UK and for about 6 months after the trip I still believed this lie. It wasn't until I asked my mum whether she ate her tampon.
She was HORRIFIED. Then she burst out laughing. I can't believe my whole class tricked me for so long.
A Nest Is Not At Home
Birds don't live in their nests.
My wife is never going to let me forget that this was a mind-blowing revelation for me.
Earth To Stars
The North Star isn't unique because of its brightness, it's unique because it doesn't move, always stays north, while the others rotate around it.
For extra trippage: the north star changes over time. The ancients had a different one from us. The point in the sky that north points to moves over time, making a complete circle every 26,000 years.
To Extend Where No Pencil Extended Before
I don't think everybody knows but I just discovered pencil extenders are a thing. I was just complaining on social media that I had a bunch of unusable pencils worn down to 2 inches, and just as I pressed send, I thought "there's probably something for that." I'm 41 and I've drawn all my life, never knew they existed.
Just Dandy
Dandelions (the yellow flowered weed) and Dandelions (the fluffy white weed) are the same plant.
I'm 29 and my dumb @$$ didn't connect that they have the same name.
Not A Bent Arrow
Oh man, for the longest time I thought the phrase "straight and narrow" was "straightened arrow" e.g. a person goes through a rough patch but now is on the 'straightened arrow' because you know, a straightened arrow flies straight and true while a warped one is all wild an erratic. Oof.
Don't get me started on my misunderstanding for an alternative word for crossing.
Bones In Your Face
That babies are born with a full set of baby and adult teeth already in their heads. Their teeth don't form when it's time for them to get them, they just push down out of their gums because they were always there.
It Was Really A Farm
When I was a kid, we had a huge dog that attacked a girl (because she was throwing rocks at him), so we had to get rid of him. My parents told me that they took him to a farm, where he would be happy and free, thinking he was dead.
Six months later, a farmer showed up at our house asking to give the dog back because he ate the cab of the farmer's truck.
Be S-Pacific
Not me but a friend of mine graduated high school and that same summer we discovered he didn't know which ocean was the Atlantic or Pacific
How Is Candle Work?
I learned this a few months ago and shared it on Reddit, which was apparently the first time many people learned this.
The wax in a candle actually fuels the flame. The heat from the flame melts the wax around it. The wick then draws the liquid wax up towards the flame. As the wax gets closer to the guy and therefore is warmed up even more, it goes from liquid to gas, and then the vapors burn to sustain the flame. Everyone seemed to think that the wax was just there to keep the wick vertical, but no, the wax actually feeds the flame.
Phone Where Is It GIF by Specks of Dust 
Clean Water GIF by Rotary International 
Visualize Video Game GIF by Dr. Donna Thomas Rodgers 
rome GIF 
China Holiday GIF by Virgin Atlantic 
Penguin Hello GIF by Pudgy Penguins 
marine GIF 
television vintage GIF 
Honda Jeep GIF 
Trick Or Treat Halloween GIF by SNICKERS 
Barbra Streisand Girl GIF 