Bitcoin Q&A: Data integrity and validation of keys

How is SHA-256 used to verify data integrity in Bitcoin? What does it mean to sign a message? Is there a difference in the validation process of compressed versus uncompressed keys?

More: https://github.com/bitcoinbook/bitcoinbook/blob/efb111026fe79d9ba2f17689463dbbca6d4a6469/appdx-bitcoinwhitepaper.asciidoc

These questions are from the August monthly subscriber session and the third session of MOOC 11, which took place on September 1st 2018 and February 14th 2019. If you want early-access to talks and a chance to participate in the monthly live Q&As with Andreas, become a patron: https://www.patreon.com/aantonop

RELATED:
What is a private key? - https://youtu.be/xxfUpIV9wRI
Public keys vs. addresses - https://youtu.be/8es3qQWkEiU
Re-using addresses - https://youtu.be/4A3urPFkx8g
Cryptographic primitives - https://youtu.be/RIckQ6RBt5E
Derivation paths and watch-only wallets - https://youtu.be/tPCN3nDVzZI
Key storage best practices - https://youtu.be/A5I55aOgX2o
Key management and inheritance - https://youtu.be/W3XADagE6P8

Andreas M. Antonopoulos is a technologist and serial entrepreneur who has become one of the most well-known and respected figures in Bitcoin. He is the author of “Mastering Bitcoin,” “The Internet of Money" series, and "Mastering Ethereum."

Follow on Twitter: @aantonop https://twitter.com/aantonop
Website: https://antonopoulos.com/

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MASTERING BITCOIN, 2nd Edition: https://amzn.to/2xcdsY9

Translations of MASTERING BITCOIN: https://bitcoinbook.info/translations-of-mastering-bitcoin/

THE INTERNET OF MONEY, v1: https://amzn.to/2ykmXFs
THE INTERNET OF MONEY, v2: https://amzn.to/2IIG5BJ

Translations of THE INTERNET OF MONEY:
Spanish, 'Internet del Dinero' (v1) - https://amzn.to/2yoaTTq
German, 'Das Internet des Geldes' (v1) - https://amzn.to/2LEiyqO
German, 'Das Internet des Geldes' (v2) - https://amzn.to/2VCzse5
French, 'L'internet de l'argent' (v1) - https://www.amazon.fr/Linternet-largent-Andreas-M-Antonopoulos/dp/2856083390
Russian, 'Интернет денег' (v1) - https://www.olbuss.ru/catalog/ekonomika-i-biznes/korporativnye-finansy-bankovskoe-delo/internet-deneg
Vietnamese, 'Internet Của Tiền Tệ' (v1) - https://alphabooks.vn/khi-tien-len-mang

MASTERING ETHEREUM: https://amzn.to/2xdxmlK

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