HTTPS and SSL

The Secure Hyper Text Transfer Protocol uses HTTP but additionally activates Web server security, in the form of Secure Sockets Layer (SSL). This means that the communications between the client and the (host) Web server are encrypted and, additionally, that the host Web server may be validated by the client using a Digital Certificate on the server.

The URL for such Web sites indicates that they are secure by the use of 'https://address' (rather than http://address), and it also features the yellow padlock in the browser's status bar.