Adam Back is a British computer scientist and crypto enthusiast who is known for being the inventor of the hashcash proof-of-work system, which is now used in Bitcoin mining. Back is the co-founder and CEO of Blockstream, a blockchain technology company that focuses on the development of Bitcoin and other cryptocurrency-related applications. He is also known for his involvement in the cypherpunk movement, which advocates for strong cryptography and privacy-enhancing technologies. Back holds a PhD in computer science from the University of Exeter and has worked for various technology companies such as Microsoft and Zero-Knowledge Systems. He has also been involved in the development of various cryptographic protocols and standards, including SSL, TLS, and SSH. Back is an active speaker and writer on topics related to blockchain technology and cryptocurrency, and he has been referenced in various media outlets including Forbes, Bloomberg, and the Wall Street Journal.