SSL and its descendent, TLS, are protocols that encrypt internet traffic, making secure internet communication and ecommerce possible.
The decades-long history of these protocols has been marked by continuous updates that aim to keep pace with increasingly sophisticated attackers. The next major version of the protocol, TLS 1.3, will soon be finalized — and most anyone who runs a website will want to upgrade, because cybercriminals are catching up.
Secure Sockets Layer, or SSL, was the original name of the protocol when it was developed in the mid-1990s by Netscape, the company that made the most popular Web browser at the time. SSL 1.0 was never released to the public, and SSL 2.0 had serious flaws. SSL 3.0, released in 1996, was completely revamped, and set the stage for what followed.