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How Carbon Dating Works

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In the movies, scientists use “carbon dating” to determine the age of ancient artifacts and dinosaur bones. But what is the real science behind carbon dating, and how does it work? Learn more at HowStuffWorks.com: http://science.howstuffworks.com/environmental/earth/geology/carbon-14.htm Share on Facebook: https://goo.gl/Vqhyah Share on Twitter: https://goo.gl/gN9pcu Subscribe: http://goo.gl/ZYI7Gt Visit our site: http://www.brainstuffshow.com SOURCES: http://science.howstuffworks.com/environmental/earth/geology/carbon-14.htm/printable http://paleobiology.si.edu/geotime/main/foundation_dating3.html
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Text Comments (627)
NightCoder (4 days ago)
And how to date a meteorite?
jelly ads (7 days ago)
Then how the heck they saying something million ago when the carbon dating is just thousands?
alvin deris (5 days ago)
there are other methods better than carbon dating. google mo tanga.
Wanmohan (15 days ago)
Surprisingly unscientific for basing all modern rockstar theories of life on earth.
Wanmohan (15 days ago)
So how can they carbon date footprints? They always use that as evidence for ancient aliens/humans, but how can you carbon date a rock?
Wanmohan (15 days ago)
And be sure that you are carbon dating the footprint and not the material of the footprint or on top of it underneath a footprint.
Wanmohan (15 days ago)
Can the carbon 14 be passed from organism to organism? In the sense that yesterday I ate a salad that had 12 thousand year old carbon 14 on it, thus when they dig my bones up they will read those carbon particles and think i am the missing link?
Wanmohan (15 days ago)
How do you know the half-life is 5 thousand and some years?
Wanmohan (15 days ago)
And before you answer by taking a sample and watching it decay and doing the best math humanly possible, i ask the second part: how do we know that they decay at the same rate through all time? If they get produced and consumed at a different rate throughout history, is it also presumably possible that the same forces that change those ratios can effect the ratio by which they are decaying?
Tommy Reusse (17 days ago)
You would think cataclysmic events on earth and air pressure differences would be able to influence carbon dating readings?
None Asdfghj (18 days ago)
t 1/2 = 0.693/k
Games TV (21 days ago)
I can carbon date a pencil.
Ricardo Arrienda (25 days ago)
Shaun White (28 days ago)
Flawed, you do not know how much carbon 14 atoms it had at the start or death.
Daniel Joseph Chiasson (1 month ago)
Are our ways of dating anything accurate, I don't think so because I know the shroud of turin is Jesus Christ
Wesley K. (1 month ago)
My cousin had a friend who planted a tree with his Dad when he was just a boy. After 40 years, that boy became a lab tech and did a sample on that tree. Carbon dating read over a MILLION years old.
OliverWinterFox (1 month ago)
3:03, Tinder's new tagline
OliverWinterFox (1 month ago)
0:43 Just like my father
OliverWinterFox (1 month ago)
He even changed his name to carbon 14
Dayal Samanpriya (1 month ago)
thank you!
Brandon J. (1 month ago)
I don't understand how scientists were able to develope this standard of years. Wouldn't you need to test these theories in order to create a functional system. And if humans haven't been around to record when the (let's just say) plant was fossilized, how can we know that is an accurate date?
BurntFossil (1 month ago)
It's all just to descredit God and has always been about that; worshipers of Lucifer rule the globe and have done for many years now, everything is to destroy Gods creation even the theory of evolution was created by a man who was anti-christian and part of a secret cult that serves Lucifer as the true god.
Brian Borell (1 month ago)
We don't. Carbon 14 dating is based on a patently false assumption about the distribution of carbon 14 in living things.
A T (1 month ago)
Who did count the carbon atoms 5730 years ago to tell us now how many particles or what ever its called is missing now? It seems unscientific and irrational for me to believe that the earth is more than 4 billion years old while carbon dating according to you can not prove existence of anything before 50,000 years ago. You call people to disbelief in God and believe your myth
Leeber Gruber (1 month ago)
Lol I was expexting a comment like this in an attempt to prove religion. If someone is murdered they can determine almost the exact hour the person died. It's accurate in hours. It's also accurate in hundreds of years , thoudands of years .. Also Carbon isn't the only method , there are so many other elements with other half life times. And there are so many more ones that don't need radioactivity. If many of these have parallels then it's very accurate. There are also many old skelets found skelets of human-like apes. This proves evolution. In fact the DNA science proves that if animals can evolve that a human can aswell, because the quran and the bible say animals were also created unique. But this is the thing ;: when european settlers reached america they took animals with them. For example the ealy years after america was discovered the spaniards bring some animals with them to america to survive : pigs. They use pigs becaus etheir noses are good to look for food. These pigs multiplied very fast because a pig can give birth to 12 pigs a year. In America did never ever live pigs before europeans came. These pigs became larger and more agressive , they really evolved in a new animal. The large black pigs.
mo county (2 months ago)
Completely false. Carbon dating is completely wrong and untrue and it doesn’t NOT work
Brian Borell (1 month ago)
+BezoomnyBratchny It's based on a false assumption about the distribution of carbon 14 in living things as well as the atmosphere. They're using an unobservable variable as a constant. SMH
BezoomnyBratchny (2 months ago)
Joseph Jones (2 months ago)
Can someone help me? Where does the half-life of carbon-14 number = 5730years come from? Everything else has been explained except for the base number which it all needs to actually work xD I’m confused lol
BezoomnyBratchny (1 month ago)
It's the amount of time that it takes half of the C-14 atoms to decay into nitrogen. And the cycle starts over each time. So an animal that has been dead for 5730 years will have half of its C-14 atoms remaining. And an animal that has been dead for 11,460 years (twice as long) will have a quarter of its C-14 atoms remaining. And so on.
whatthe (2 months ago)
How was the half life calculated? How wold you know what was the 100% amount of carbon 14 in a fossil? Also what was the carbon 12 to carbon 14 ratio 50k years ago? has this ratio been same for millions of years?
Rahim LaQuica (27 days ago)
Luqfire See How would they know that it decays at a regular and constant pace? It may lose 1% of its carbon 14 rate the first year and then 3% the next year (random numbers).
Luqfire See (2 months ago)
You can measure the half life by using extrapolation; say that you measure the amount of particles having decayed in a year or so from a sample and recording it against a graph where you imagine that there was synchronicity/ a pattern in the events. Or you can use cross multiplication. Moreover, if you do basic chemistry, you'll realise that there is always a never changing ratio, from the Relative Abundance calculation. Hope this helps. Peace.
Shubham Rai (2 months ago)
well sir
Salman Machwal (2 months ago)
Nuclear medicine
teodelfuego (2 months ago)
I love how scientifically illiterate commenters are so dismissive of scientists in comments they could only make using the technology afforded them by scientists. "Science is bullshit! I know better than them! Now, time to charge the lithium-ion battery in my hand held computer/phone/camera/GOS device."
jiminology (2 months ago)
i still don't understand dude I'm about to have an early life crisis
BezoomnyBratchny (2 months ago)
The natural state of a carbon atom is for it to have 6 protons and 6 neutrons. 6+6=12. So it's atomic mass is 12 and we call it carbon-12 or C-12 for short. There are also carbon-13 or C-13 atoms which have 6 protons and 7 neutrons. And then there's carbon-14 or C-14 which has 6 protons and 8 neutrons. Now, there is a certain ratio of C-12 to C-14 that exists. If it makes it easier, we can think of it as a percentage rather than a ratio. We can also use some (fake) round numbers to make it easier. And we'll also just pretend that C-13 doesn't exist because it's not relevant to this. So let's say that for all the carbon atoms that exist, 90% is C-12 and 10% is C-14. So if we take 10 carbon atoms, 9 of them will be C-12 and 1 of them will be C-14. That same percentage will be true in every living organism. Let me explain. There's a complex ecosystem with a food chain. All living things either eat other living things or get eaten by other living things or both. So let's say that the carbon atoms in you are 90% C-12 and 10% C-14. You eat a fish. The carbon atoms in the fish were also 90% C-12 to 10% C-14. So because the amount of carbon atoms that you took in by eating the fish were 90 to 10, the total amount of carbon atoms in you remains 90 to 10. You took a bunch of extra C-14 atoms into your body which would throw the balance off but for every C-14 atom you took in, you took 9 C-12 atoms in so it balances it back out. And the fish had 90 to 10 in it's body because the things that it ate had 90 to 10 and so on and so on. So all life ends up with the same percentage of C-12 atoms as each other and the same percentage of C-14 atoms as each other. When an animal dies, something starts to happen. Because of the two extra neutrons in C-14 atoms, they are very unstable. Through a process known as beta decay, 1 of it's neutrons turns into a proton. So it then has 7 neutrons and 7 protons. An atom with 7 protons and 7 neutrons is nitrogen. So C-14 atoms decay into nitrogen atoms. The time that it takes for this decay to take place occurs at a constant rate. C-14 has a half life of 5730 years. This means that it takes 5730 years for half of the C-14 atoms to decay into nitrogen. So if an animal died 5730 years ago, 5% of it's carbon atoms would be C-14 and the other 5% would have decayed into nitrogen. The same thing then happens again. It starts a new cycle. So if an animal has been dead for 5730 years, it has half the C-14 atoms that it started with and if an animal has been dead for 11,460 (twice as long), then it has a quarter of the C-14 atoms that it started with. So knowing all this, if the amount of C-14 atoms in a dead animal and the amount of C-12 atoms in a dead animal are both counted and then those two numbers are compared, it's possible to do some calculations to work out how long it would take to go backwards and end up back at 90% C-12 to 10% C-14 and whatever that number is, that is how long ago that the animal died.
Blake Marb (2 months ago)
Wow!!! I wish just Like Carbon Dating, i could access information from a woman with whom im Woman Dating..😊😊😊
Liontari Music (2 months ago)
3:02 so carbon dating is gonna help me find a potential mate's information. i feel a little odd about the "long dead for thousands of years" part but hey, never judge a book by its cover.
Chieko Hoki (2 months ago)
I think I'm dyslexic. I totally read Brian stuff, and then he said his name was Josh. I was like "why would you false advertise your name and then rat yourself out, it's such a needless lie for no gain...."
Paul McMullan (2 months ago)
So why aren't dinosaur bones being carbon dated when soft tissue in dinosaur bones is being discovered all over the world. That last bit about atomic bombs and post industrial revolution atmospheric carbon was a totally fake attempt to distract clear thinking individuals from the facts.
Garrick Dean Lucasan (2 months ago)
Carbon-14 has a half life of 5730years. in 5730 year, half Life 3 will release. Half Life 3 confirimed
Keith Lucas (3 months ago)
Radiometric dating is flawed because of the assumption of decay rates remaining fixed. Evidence for the period of accelerated decay is found in zircon crystals. Zircon crystals in granite contain radioactive uranium-238, which decays into lead over time. As the uranium decays, helium is produced in the crystals. Helium escapes from the crystals at a known, measurable rate. If those rocks were over a billion years old, as evolutionists claim, the helium should have leaked out of the rock. The presence of lots of helium in the crystals is evidence in support of a young earth. Adding the red/blue shift in our sun and the absolute fine tuned solar system we live in invalides any evolution and is suggested by Stephen Hawkings. There is a list of atheists who also support this and are leaning toward this planet "being seeded" by "outside sources". Looking at the discoveries of Ron Wyatt, I'd say the "culprit" that did this has been found.
Hyun Doh (3 months ago)
there are too many variables in Carbon dating and based on weak assumptions. it's not exact.
Michael Fitzgerald (3 months ago)
No. This does not explain it at all. It only gives the easy-to-find outlines of the principles involved.
Andre Lypher (3 months ago)
He didn't even explain anything I call bullshit
Cristian Daniel Popescu (3 months ago)
Sometime does work ,sometime doesnt work: they have founded C 14 in the dinos bones
IMAGINARY VIEWS (3 months ago)
How do we know that the C12 and C14 atoms ratio in the atmosphere is same since the past years ?
Nicky J (3 months ago)
I believe in carbon dating, but it would be best to only date carbon 12. Carbon 14 is too unstable and eventually changes form - no-one wants such a complicated relationship. 😊
Alexis Boyce (3 months ago)
If you turn the speed to 1.25 he sounds like a normal human talk
Wayne Renee (3 months ago)
Isn't it an assumption that carbon 14 has been the same number in the atmosphere for thousands of years? How long have we measured it?
Wayne Renee (3 months ago)
+BezoomnyBratchny How much c14 was in the atmosphere 4000 years ago?
BezoomnyBratchny (3 months ago)
No. It is calibrated with various other methods at different points in history.
Edward Hayes (3 months ago)
You are forgiven. LOL!
Keshav Pisal (4 months ago)
I am from India
Kieran Donnelly (4 months ago)
I want to know how scientists date things that cant be carbon dated, like how they think a gamma ray burst destroyed the ozone 400 million years ago etc, i cant find any explantion anywhere?
The sound of the chalk is the only reason I cannot watch this. I hate that sounds. It causes me to spaz out.
Jøshüa 115 (4 months ago)
Hey Science man If carbon 14 has a life time of 5730 years then why Did we find carbon 14 in dinosaur bones That are supposed to be 65 million years old Just seems like more reasons to believe in a Young earth
BezoomnyBratchny (3 months ago)
Can you provide a single example of an uncontaminated dinosaur fossil that contains carbon 14?
Wk Schwenke (4 months ago)
And that is why carbon dating is unreliable... this guy makes so many assumptions... and even this guy was correct, if the entire world was made of carbon 14, it would be all gone within a million years... yet they claim to find carbon 14 in dinosaurs they claim to be 50 million years old... SMH
Troy Cook (4 months ago)
I've always had this one feeling... the way creationists have faith in creation it is equal to the same Faith scientists have to eventually put in science. Either way regardless of what side of the line you're on , both parties eventually have to believe and use faith. Who's to say that even before scientists and scientific theory etc...(oh Let's just say a hundred thousand years ago.), that during just one of the global Ice Age events( among many other events of the like) etc, that the atmosphere of the Earth wasnt completely different or even a smidgen off than it is today. Cuz the slightest difference would change the entire set of criteria for your scientific tests. And in order for science to be 100% factual then your tests need to be 100% untainted or uncontaminated. No scientist in good conscience could say or even prove that. And there's a scientific fact right there! So it really doesn't matter what side of the line you're on... Either way eventually you have to believe or have faith in the stance you take.
Sarcasm ⃝ (5 months ago)
Why is Dirk Nowitzki discussing carbon dating again??
Hon Estman (5 months ago)
Is it at all possible that carbon 14 exist in anything a million years old?
Hon Estman (5 months ago)
Don't plants actually grow faster and put out more oxygen when exposed to greater amounts of CO2. What I mean is that if you put a plant in a room and upped the CO2 , wouldn't that plant grow faster ? If so, do you think the atmosphere will still be jacked up by the extra CO2 that humankind generates from their activities?
Sarah Poynter (5 months ago)
Okay I’m a dummy but can someone explain how we know he half life?
Tom Schneider (5 months ago)
Not at all, you only fall asleep if you loose interest in the issue. Perhaps you were looking for entertainment instead of knowledge
Miss Ambivert (5 months ago)
How do they know the actual amount of carbon 14 present in the organism?
BezoomnyBratchny (5 months ago)
An accelerator mass spectronomy machine counts them. Carbon ions are emitted from the sample which the machine then separates into C14 atoms and C12 atoms. It does this by removing electrons from them so that they go from having a negative charge to a positive charge. They are then accelerated around a magnet. Because the C14 atoms weigh more than C12 atoms, they come out the other end at a different angle to them so that they can be counted separately from the C12 ones.
Payton Pryor (5 months ago)
The atmosphere of earth has changed over time, wouldn't the rate of production of carbon 14 and 12 atoms have changed over time? Sure they are formed at a constant rate now, the atmosphere is relatively stable now; the atmosphere has still changed slowly but still relatively dramatically over time.
Billy Lucius (5 months ago)
Look at the discovery of the body of King Richard III of England. We know exactly the day he died (22 August 1485) at the Battle of Bosworth Field yet Carbon 14 was some 70 years off. I would think that such a discovery would calibrate the calculations but nobody seems to care.
Austin (5 months ago)
Bangalore's Hydro Home (5 months ago)
This feels like an actor delivering his lines.. Not knowing what it is... But Josh, I'm a big fan of how stuff podcast man,
Midas Haltzern (5 months ago)
Knowing this it sounds ridiculous that dinosaur fossils are carbon dated. There are too many factors in the environment and over time that can mess with the calculation. The soil composition around the bones, the atmosphere etc. How are we supposed to believe these guys?
Hayden Case (5 months ago)
Midas Haltzern Well to be fair here, dinosaurs fossils are dated with other methods such as potassium 40 and uranium -lead dating, so fossils like these can't be carbon date, that's why there are other methods.
Erdindar (5 months ago)
Omgosh this guy looks like Bruce Banner from the Avenger's movie! He even sounds like him
Indranil Jana (5 months ago)
Critical technology
aTYPICAL (5 months ago)
how can they say that the ratio of 14-c and other carbons is constant as long as the organism is alive and eating, when there are thousand and thousands of variables out there that may affect the result, this is a pretty baseless opinion, I can't believe how carbon 14 dating got accepted in today's science when it's results are nowhere close to accurate
Rosanna Miller (5 months ago)
How do you KNOW that about the Carbons? Carbon has a half life of 5730 years? You people are the sheep with a blind faith. Just because you Appeal to Authority it does not make you Intelligent. It makes you gullible hypocrites. Because for all of my life the Atheists have accused the believers of blind faith when they are the ones who have blind faith. Guess what? I can memorize a bunch of random numbers based on nothing concrete and regurgitate them forever, but without proof to back up the so called stats/facts (random numbers are not proof of the age of something), what I repeat still is not true. Even if everyone agrees with me. I am not calling you a liar yet, I just want you to show the proof for your claims. And you turning and expecting me to prove otherwise further shows how dishonest you really are! And shame on you.
J Ovesen (5 months ago)
Rosanna Miller Of course I demand proof that the thing of which you speak exists. Why wouldn’t I? Wait, you think I am being a hypocrite? Right? Science is not about “proving things”. Science creates models that *explains* that which have been observed. Science doesn’t claim evolution exist. We observed that life evolves, and science seeks to explain why. You claim a god exists. Period. You can’t tell the difference?
Rosanna Miller (5 months ago)
+J Ovesen right. Yet you demand proof of God. You go seek God because your science isn't saving you from Hell.
J Ovesen (5 months ago)
If you knew what science is, you wouldn’t be asking for “proof”. Go back to school.
blindwelcome (5 months ago)
wonder why he thinks it a future problem when its going on now?
The River of Faith (5 months ago)
Do you know of the single scientific dating method used for accurately dating any object? If so, what is it, and how does it work? I know what it is. It’s quite simple. Do you know?
Noobist (6 months ago)
yall know that volcanos spew many times more carbon than any atomic bomb ever made right? so, modern human activity probably had little to no effect on the amount of carbon in the air.
J Ovesen (5 months ago)
That’s a non sequitur.. How does it follow that just because a volcano pumps out carbon, anthropomorphic carbon has no effect? If humans were carbon neutral, would that make the carbon from the volcano more or less of a problem?
IThinkWithMy Dick (6 months ago)
1:29 No need for humans to murder animals for meat.
Alex Thompson (6 months ago)
Swamp Hawk (6 months ago)
When I first read the title, my stupid brain thought this was a new way to meet singles, and I just hadn't heard of it yet.
Sara Saliaga (6 months ago)
Thx I have a test tomorrow
Rebel (6 months ago)
Atoms don't disappear through decay process dummy, a decayed atom is simply less radioactive.
Chris Ackley (7 months ago)
Can soler flare effect rate
Anita Tromp (7 months ago)
So if I keep eating old fossils and they carbon date me one day t's going to show i'm millions of years old? :P Gonna start right now
Vasto Lorde (2 months ago)
Actually the opposite, pretty sure the more carbon 14 you have, the more recent you are. Shit you might have discovered time travel
Michael Ruiz (7 months ago)
" Nitrogen becomes carbon."  If there was less nitrogen in the atmosphere  for any real length  time would that change test results?
Ravi Bassett (8 months ago)
Anyone here for school?lol
globalswitch17 (8 months ago)
Lol youve gotta be a fuckin moron if you beleive this
Hayden Case (8 months ago)
globalswitch17 So please tell how does this makes him a fuckin moron anyway?
ronald22176 (8 months ago)
then how did the fossils end up million years before, if the carbon dating just have a limit of only thousands of years?
Alex Thompson (6 months ago)
I think they use other dating methods but it seems strange since ink, dino blood cells and soft tissue have been found in things dated dozens of millions of years ago.
Leanne Fresquez (8 months ago)
This guy has no energy or excitement. He's so boring. Liven up some guy
paul spring (8 months ago)
3:36 explains more than anything before it...
paul spring (8 months ago)
Just for reference: https://youtu.be/NkQtmO-PX2w
Hayden Case (5 months ago)
paul spring Kent is a lair, you know that, right?
paul spring (8 months ago)
Found my new "Go To Sleep" video. Sweeeeet
Clara Huang (8 months ago)
could you do a video on how electron spin resonance dating works
ayesha khan (8 months ago)
so great sir
Anthony Ortiz (8 months ago)
his use of the word roughly worries me. Ive always known accepted timelines are wayyy off.
Mad Michael (8 months ago)
That's all good but how do scientists measure these things? What machines or equipment do they use to find what you said? Can I go around and start carbon date things if I know more details? (it's a rhetorical question)
adankseason ADS (9 months ago)
Is this stoner science or something? His accent/tone is surprising to me lol.
Kamunu Odomankoma (9 months ago)
Carbon Datin is a lie. No different than gravity.
Kamunu Odomankoma (8 months ago)
Hayden Case A human.
Hayden Case (8 months ago)
So what are you exactly?
Kamunu Odomankoma (8 months ago)
Hayden Case I’m not an anythin. I only deal with observable, provable facts. I am not a flat earther, but I do know that I am not a believer of the factless theory that we are on some basketball spinnin a million miles an hour thru space after a random explosion exploded for no reason out of nothingness that proceeded to create everythin in perfect order. That’s what I know I am not. Anythin else?
Hayden Case (8 months ago)
So are you a creationist , are you a flat earther or are you both of them?
Kamunu Odomankoma (8 months ago)
Hayden Case U can read can’t u.
Georgi Dimov (9 months ago)
It takes faith to claim that the meteorites have no other source of half-dead material, an interesting religion is evolution. Also, C14 is not the same amount as it was 50 years ago and it was even less than 5,000 years ago, so finding a dead animal and not knowing how much C14 there was when it died because you do not know when it died how you calculate it without faith and imagination? Equilibrium of C14 is not yet on the planet and is still growing.
Jake Gopita (9 months ago)
honestly, i don't get it what carbon dating means because the speaker is not good at all in explaining, it should be clearly w/ concrete example not just 50, 000 yrs what about the Dino which live million yrs ago....lol.. he should have comparison or model to visualize the concept of carbon dating...
The Muslim Dude (9 months ago)
What if the carbon 14 dating evidences were currupted in the past too? duo to natural geothermal activity or by other means?
rich lopez (9 months ago)
For dry itchy eyes use clear eye... wooooowwww! This guy should do visine commercials
SerElbass (9 months ago)
So... is it inaccurate to predict the times of the dinosaurs? Or is there another method? Just a noob with questions!
Sean-Justin Lattimore (9 months ago)
How do scientists account for changing conditions? Surely this would change the decay rate.
D T (9 months ago)
Did I forget to lock my desk mmmm oh yeah Carbon 15
Pollution X (9 months ago)
how do you know how much carbon 14 did it originally have?
FondofHonda (10 months ago)
Could a big solar flare(s) effect the ratio of carbon 12 and 14?
crazy ZONE (10 months ago)
Why don't you add subtitles yar....many may not understand your slang
YourTube (10 months ago)
Awesomely explained carbon dating A small suggestion,just add a subtitle
علي القحطاني (10 months ago)
I can only imagine the amount of math that was needed to calculate how old is earth..
Josué Artaud (11 months ago)
Is the earth 6000 + 18 year old or still 6000?
dakonblackrose (6 months ago)
It's 6051
Tony4nderson (6 months ago)
According to the jewish calendar it's 5779 years 😉
Tuxedo Steve (8 months ago)
Josué Artaud it was never 6000 Years old.
MrBonners (11 months ago)
Dinosaur 'bones' are rock, you can not carbon date rock.
litlikeiz (11 months ago)
Lamia Kerri (11 months ago)
It's useless to answer questions asked by kids here. They still believe in fairy tales. Complex facts explained by science need higher intelligence to understand them. So weaker minds, just go and read your fairy tales and stop asking questions on basic stuff here. xD

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