What is the difference between TLS and SSL?

Secure Sockets Layer, or SSL, was the original protocol for encrypting web communications, but all versions including SSL 3.0 have known vulnerabilities and are deprecated. Transport Layer Security, or TLS, is the successor protocol that provides the same function with stronger security. Current recommended versions are TLS 1.2 and TLS 1.3. TLS 1.3 removed support for older insecure cipher suites, reduced the handshake to one round trip for faster connections, and made forward secrecy mandatory. Although people still say "SSL certificate," the actual protocol used is TLS.