Which security protocols is used to secure web transactions?

Ssl (secure sockets layer) -the secure socket layer is used to establish a secure communication connection between two tcp-based machines. this protocol uses the handshake method. when a connection request is made to the server, the server sends a message back to the client indicating a secure connection is needed. the client then sends the server a certificate indicating the capabilities of the client. the server then evaluates the certificate and responds with a session key and an encrypted private key. the session is secure after this process. reference: mike pastore and emmett dulaney, security+ study guide, 2nd edition, alameda, sybex, 2004, p 365