How Hashcash Works: Proof of Work Before Bitcoin

Quick Answer: Hashcash, created by Adam Back in 1997, introduced Proof of Work to combat email spam by requiring senders to solve a computationally asymmetric puzzle. By forcing senders to compute a hash with leading zero bits, it imposed a tiny delay on single emails while rendering mass spam computationally infeasible—a principle Satoshi... Weiterlesen: How Hashcash Works: Proof of Work Before Bitcoin