RSA 
The public key encryption algorithm created by Ron Rivest (R), Adi Shamir (S), and Leonard Adleman (A), and licensed by their company, RSA Data Security. This public-key algorithm has been adopted for many types of encryption, from digital signatures to the SSL (Secure Sockets Layer) used to protect transmissions between Web browsers and servers. Even several commercial encryption packages, such as PGP, use the RSA algorithm.