Why Did Bitcoin Choose SHA-256?

SHA-256 was chosen because it is a well-established, highly secure cryptographic hash function standardized by the U.S. National Security Agency (NSA). Its widespread use and proven resilience against collision attacks made it a reliable choice for the integrity of the blockchain.

Furthermore, the algorithm was public, allowing for open-source verification and trust. It provides the necessary difficulty adjustment for the Proof-of-Work mining process.