What is an SSL certificate?

[Aussie Bob]

SSL means Secure Socket Layer. Secure Sockets Layer (SSL), are cryptographic protocols which provide secure communications on the Internet for such things as web browsing, e-mail, Internet faxing, instant messaging and other data transfers.

SSL is most commonly used in ecommerce, where a secure (https) connection must be established, for the movement of sensitive data between the user and the server.

A more detailed explanation of SSL is here.