Adam Back is a British cryptographer, cypherpunk, and the CEO of Blockstream, a blockchain technology company. Here are some key points about him:

- **Birth and Education**: Born in July 1970 in London, England, Back taught himself Basic programming on a Sinclair ZX81. He completed his A levels in advanced mathematics, physics, and economics, and later earned a PhD in computer science from the University of Exeter, focusing on distributed systems.

- **Hashcash**: He is best known for inventing Hashcash in 1997, a proof-of-work system initially designed to combat email spam. This concept was later adapted and cited in the Bitcoin whitepaper by Satoshi Nakamoto for Bitcoin's mining process.

- **Bitcoin and Cryptocurrency**: Back was one of the first individuals to receive an email from Satoshi Nakamoto and has been involved in Bitcoin since its early days. He has been associated with various aspects of Bitcoin development, including being mentioned in the Bitcoin whitepaper.

- **Blockstream**: In 2014, Adam Back co-founded Blockstream, where he serves as CEO. Blockstream focuses on blockchain technology, contributing to Bitcoin Core, developing the Lightning Network, liquid sidechains, among other projects.

- **Influence and Controversy**: Back is often discussed in the cryptocurrency community, not only for his technical contributions but also for his influence on Bitcoin's development. There have been speculations about his identity being linked to Satoshi Nakamoto, though he has denied these claims.

- **Public Presence**: He is active on social media, particularly known for his Twitter presence where he engages with the crypto community, often leading to debates and discussions about Bitcoin's future and implementation.

These insights are gathered from various sources including Wikipedia, Cointelegraph, and other web articles discussing his contributions to cryptography and blockchain technology.