Bitcoin Q&A: What is difficulty targeting?

How does difficulty targeting work? What determines the desired pattern? Should difficulty re-targeting still happen every 2016 blocks? Could difficulty changes (and hence profitability changes) make all miners drop out?

These questions are from the MOOC 7.2 and 9.2 sessions, which took place on February 26th 2017 and February 23rd 2018 respectively. Andreas is a teaching fellow with the University of Nicosia. The first course in their Master of Science in Digital Currency degree, DFIN-511: Introduction to Digital Currencies, is offered for free as an open enrollment MOOC course to anyone interested in learning about the fundamental principles.

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 mining? - https://youtu.be/t4p4iMqmxbQ
Miners, pools, and consensus - https://youtu.be/JHz7LM4ncLw
The mining process - https://youtu.be/L4Xtau0YMJw
Nonces, mining, and quantum computing - https://youtu.be/d4xXJh677J0
Honest nodes and consensus - https://youtu.be/KAhY2ymI-tg
Genesis block and coinbase transactions - https://youtu.be/strhfzJ56QE
Proof-of-work changes - https://youtu.be/AcaktuPdQrc
SegWit and fork research - https://youtu.be/OorLoi01KEE
What is the role of nodes? - https://youtu.be/fNk7nYxTOyQ
Why running a node is important - https://youtu.be/oX0Yrv-6jVs

Andreas M. Antonopoulos is a technologist and serial entrepreneur who has become one of the most well-known and respected figures in bitcoin.

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

He is the author of two books: “Mastering Bitcoin,” published by O’Reilly Media and considered the best technical guide to bitcoin; “The Internet of Money,” a book about why bitcoin matters.

THE INTERNET OF MONEY, v1: https://www.amazon.co.uk/Internet-Money-collection-Andreas-Antonopoulos/dp/1537000454/ref=asap_bc?ie=UTF8

[NEW] THE INTERNET OF MONEY, v2: https://www.amazon.com/Internet-Money-Andreas-M-Antonopoulos/dp/194791006X/ref=asap_bc?ie=UTF8

MASTERING BITCOIN: https://www.amazon.co.uk/Mastering-Bitcoin-Unlocking-Digital-Cryptocurrencies/dp/1449374042

[NEW] MASTERING BITCOIN, 2nd Edition: https://www.amazon.com/Mastering-Bitcoin-Programming-Open-Blockchain/dp/1491954388

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

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