A handshake is a process in which a browser authenticates a server’s SSL or TLS certificate. This process authenticates both parties, then exchanges cryptographic keys.
The SSL handshake is the process in which a client and server establish the encryption algorithms and secret keys they will use to communicate with each other securely, and exchange and validate each other’s digital certificates.
Transport Layer Security (TLS) is the upgraded version of SSL that fixes existing SSL vulnerabilities.