The first computer virus that was released outside the lab was the Elk Cloner virus, written by high school student Rick Skrenta back in 1982 for Apple II computers. According to Information Security Stack Exchange: HTTPS is HTTP-within-Secure Sockets Layer (SSL)/Transport Layer Security (TLS). SSL (TLS) establishes a secured, bidirectional tunnel for arbitrary binary data between two hosts. Both TLS and SSL are intended to provide confidentiality and message authentication over a network link. In the network protocol stack, TLS and SSL run on top of TCP/IP, but below network protocols such as HTTP. Symmetric key cryptography uses the same key to encrypt the text and to decrypt the text. A Message Authentication Code (MAC) is different from a Digital Signature in that it uses a secret key that is shared by both sender and receiver, whereas a Digital Signature is encrypted using a private key and decrypted using a public key.