is a hybrid cryptosystem that combines some of the best available cryptographic algorithms and has become the open-source de facto standard for encryption and authentication of e-mail and file storage applications.

The correct answer is PGP i.e  "Pretty Good Privacy" .

Explanation:

Pretty Good Privacy is an encryption algorithm that gives the database interaction with the confidentiality and authorization.Pretty Good Privacy is security algorithm which gives the security into the mail . login ,decryption ,encryption are the example of the "Pretty Good Privacy" .

Pretty Good Privacy  is a type of  hybrid cryptosystem that incorporates cryptographic algorithms and it has de facto open source standard for the mail and the file storage .