https://en.bitcoin.it/wiki/Secp256k1 + https://bitcoin.stackexchange.com/questions/8443/where-is-double-hashing-performed-in-bitcoinquoting note1t92…w6muElliptic Curve Digital Signature Algorithm or ECDSA is a cryptographic algorithm used by Bitcoin to ensure that funds can only be spent by their rightful owners. It is dependent on the curve order and hash function used. For bitcoin these are Secp256k1 and SHA256(SHA256()) respectively.