The Bitcoin blockchain protocol for uses public key cryptography for digital signatures and cryptographic hash functions, details of which will be explained below. The cryptographic algorithm used in bitcoin futures is called elliptic curve cryptography. It is a type of asymmetric cryptography that is considered more efficient compared to classic RSA cryptography. While elliptic curve cryptography provides the same level of security like RSA, it needs less computation and smaller key size, thus reducing storage and transmission requirements.