HTTPS

Hypertext Transfer Protocol over Secure Socket Layer, or HTTP over SSL, is a web protocol that encrypts and decrypts user page requests as well as the pages that are returned by the web server. HTTPS uses SSL as a sublayer under its regular HTTP application layering. (HTTPS uses port 443 instead of HTTP port 80 in its interactions with the lower layer, TCP/IP.) SSL uses a 40-bit key size for the RC4 stream encryption algorithm, which is considered an adequate degree of encryption for commercial exchange.