Secure Sockets Layer (SSL) is a cryptographic protocol designed to provide communications security over a computer network. This tag should be use when dealing with SSL certificate involving macOS or iOS
SSL was invented in 1994 by Netscape Communications to secure communications between clients and server applications over an unprotected networ. Several versions of the protocols find widespread use in applications such as web browsing, email, instant messaging, and voice over IP (VoIP). Websites can use SSL to secure all communications between their servers and web browsers.
SSL uses the Message Authentication (MAC) algorithm - a message authentication code (MAC) is a short piece of information used to authenticate a message and to provide integrity and authenticity assurances on the message. Integrity assurances detect accidental and intentional message changes, while authenticity assurances affirm the message's origin.
On macOS, certificate signing request for SSL are generated and then installed in Keychain Access.