New video! Ever wonder how Bitcoin (and other cryptocurrencies) actually work?

I loved this article. The premise is hilarious, and the execution is enlightening.

3blue1brown

FYI - Mining BitCoin with Pencil and Paper at 0.67 hashes a day <a href="http://www.righto.com/2014/09/mining-bitcoin-with-pencil-and-paper.html" rel="nofollow noopener" target="_blank">http://www.righto.com/2014/09/mining-bitcoin-with-pencil-and-paper.html</a>

Chase Turner

Hey, thanks for this video. It was a question I have had for a long time and a some point I forgot about it. I'm really glad I found this.

Incredible as always, Grant! I always let people know about your videos - never mind giving you a plug. It's really interesting, you touched on this a bit, about if you owned about half of the computing power, you could control the blockchain. I heard this actually has the name 51% attack - it might be a cool concept to link to! <a href="https://learncryptography.com/cryptocurrency/51-attack" rel="nofollow noopener" target="_blank">https://learncryptography.com/cryptocurrency/51-attack</a>Edit: I also had a follow-up question: "the first discovered solution to each block is the one that the entire network decides to accept." This seems to conflict with what you were saying - does it actually wait or accepts the first solution? And are there multiple solutions? From: <a href="https://www.dailydot.com/business/bitcoin-51-percent-attack/" rel="nofollow noopener" target="_blank">https://www.dailydot.com/business/bitcoin-51-percent-attack/</a>

Josh B.

Even though I took a grad level crypto course, this video was really interesting to watch. More videos like that! :) I bet that with the current hype about the various cryptocurrency related stuff, you'll also get plenty new subscribers and views on your great channel

I...suppose I never have. Boy, that feels a bit strange just thinking about. I kind of like that the pi creatures are gender ambiguous (at least in my view), and I feel like as soon as hair is put on there it ends up implying that everyone without hair is male.

3blue1brown

Thanks, I really appreciate that. I think its many little personal recommendations like that that can really help a channel to grow.

3blue1brown

Thanks so much for making your videos! I recommend them to all of my friends!

Hi Grant, out of curiosity, have you thought of giving hair to your pi creatures ;-)

MedNait

Exceptional.

Illuminati Games

I definitely think I'll cover elliptic curves at some point. There's just so many different angles you can approach it from.

3blue1brown

If you’re doing videos on cryptography, what about a video on elliptic curves? Another request is Lorentz transformations and the Minkowski spacetime. The math looks extremely awkward, there surely must be some point of view from which the math is as natural as Galilean relativity.

Roman Odaisky

Awesome job. I recently picked up "Blockchain for Dummies" expecting to find this kind of explanation, but to my dismay it basically skipped over all explanation of what blockchains actually are and talks at length about the different kinds and what you can do with them. There was one thing in the video that mildly confused me. At 17:00 a block chain is depicted with pointers to the right. My software-engineer brain immediately said "That's a linked list with the head (which must be the newest entry) at the left." Of course that isn't what was being depicted at all -- the arrow means "the hash of this block is stored there" and the newest entry is on the right. This wasn't a huge deal, but I think it would have been clearer if to the right of each block had been a tall right curly brace from which the arrow emerged, capturing the notion of hashing while also not looking like a linked list. That feedback aside, this is great stuff!

Nicholas Sterling

This is amazing. I started learning about cryptocurrencies just before the huge hype wave hit this year, and just when I was considering actively doing research on the field you just go and make an awesome video about it. The synchronicity in my life makes me smile, thank you for that.

André Mello

The reward is built into the protocol, there is no need for any decision on who gets it or how much...

I found myself wondering how the amount rewarded to miners is decided upon in a decentralized way. I assume it's part of the protocol where miners working on the same block are able to trust the winner and form some majority vote on the amount rewarded? Or is the amount rewarded introduced into the blockchain somewhere so anyone can check what the current reward should be? Anyway, I'm now curious enough to Google these things haha. Thanks, Grant!

Duncan Fairbanks

Yeah, well, sorry for insinuating that you run out on your debts ;)

3blue1brown

Thanks so much! I really appreciate it.

3blue1brown

I'm not sure I see the typo, maybe I am still blind....I intended for these amount to reflect his "running balance" in the sense of how much total money he has at the point.

3blue1brown

At the very least, there is the mining reward as a single transaction. But there's no need to "fill" the whole block. If you find a valid proof of work, you could broadcast one that just has a couple transactions, or even zero. You'd pick up fewer transaction fees, but there's nothing inherently wrong with it.

3blue1brown

I'm a bit confused as to what happens if no one transacts for a couple days. Don't you need transactions to fill the blocks in order for it work? And likewise, what if people were buying and selling items with bitcoin, but no one was mining any bitcoin? I assume "mining a special block" is the same as getting bitcoin. How are we sure that 2400 transaction happen at the same rate as mining blocks?

Doug Dee

Grant, Check the video at about 8:32, it looks like you made a numerical typo under "Charlies running leger." For the first time I am getting the idea behind cryptocurrency. Thanks

The way you explain these complex topics is incredible. I'm very happy to have pledged you.

Oh Exciting! Love the topic, and this is the first I've seen of the math behind it