But how does bitcoin actually work?

The math behind cryptocurrencies.
Help fund future projects: https://www.patreon.com/3blue1brown
An equally valuable form of support is to simply share some of the videos.
Special thanks to these supporters: http://3b1b.co/btc-thanks
This video was also funded with help from Protocol Labs: https://protocol.ai/join/

Some people have asked if this channel accepts contributions in cryptocurrency form. As a matter of fact, it does:
http://3b1b.co/crypto
ENS: 3b1b.eth

2^256 video: https://youtu.be/S9JGmA5_unY

Music by Vincent Rubinetti: https://soundcloud.com/vincerubinetti/heartbeat

Here are a few other resources I'd recommend:

Original Bitcoin paper: https://bitcoin.org/bitcoin.pdf

Block explorer: https://blockexplorer.com/

Blog post by Michael Nielsen: https://goo.gl/BW1RV3
(This is particularly good for understanding the details of what transactions look like, which is something this video did not cover)

Video by CuriousInventor: https://youtu.be/Lx9zgZCMqXE

Video by Anders Brownworth: https://youtu.be/_160oMzblY8

Ethereum white paper: https://goo.gl/XXZddT

Timestamps:

0:00 - Introduction
2:25 - Ledgers and digital signatures
7:21 - The ledger is the currency
10:06 - Decentralization
12:26 - Cryptographic hash functions
14:38 - Proof of work and blockchains
19:42 - Double spending
21:41 - Block times, halvenings, and transaction fees
24:40 - Thanks

Thanks to these viewers for their contributions to translations
Italian: @lcl45

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Animations are largely made using manim, a scrappy open-source python library. https://github.com/3b1b/manim

If you want to check it out, I feel compelled to warn you that it's not the most well-documented tool, and has many other quirks you might expect in a library someone wrote with only their own use in mind.

Music by Vincent Rubinetti.
Download the music on Bandcamp:
https://vincerubinetti.bandcam....p.com/album/the-musi

Stream the music on Spotify:
https://open.spotify.com/album..../1dVyjwS8FBqXhRunaG5

If you want to contribute translated subtitles or to help review those that have already been made by others and need approval, you can click the gear icon in the video and go to subtitles/cc, then "add subtitles/cc". I really appreciate those who do this, as it helps make the lessons accessible to more people.
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3blue1brown is a channel about animating math, in all senses of the word animate. And you know the drill with YouTube, if you want to stay posted on new videos, subscribe, and click the bell to receive notifications (if you're into that).

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