The concept was adapted from digital tokens by Hal Finney in 2004 through the idea of "reusable proof of work" using the 160-bit secure hash algorithm 1 (SHA-1). 1 ...

Older algorithms like MD5 and SHA1 have vulnerabilities that may or may not be a problem for you. If you need a secure hash, it is probably best to avoid them anyway.

The private key secures transactions, ensuring only its holder can authorize transfers. • SHA-256 Hashing: This one-way hashing algorithm secures blockchain integrity and prevents tampering.