What is HTTPS?
Hypertext Transfer Protocol Secure or HTTPS is an extension of the HTTP or Hypertext Transfer Protocol. HTTPS is used for secure communication over a computer network and is used for encrypted communication between a web browser (client) and a web server (host). The emphasis is on "encrypted"; early data traffic on the World Wide Web started off as anything but secure.
HTTPS is especially important on unsecured networks and networks that may be subject to tampering. In this protocol, the communication protocol is encrypted using TLS (Transport Layer Security) or, SSL (Secure Sockets Layer). Therefore it’s also referred to as HTTP over TLS, or HTTP over SSL.
Insecure networks, such as public Wi-Fi access points, allow anyone on the same local network to do packet sniffing and search for sensitive information that is not protected by HTTPS. HTTPS is also important for connections on the Tor network, as malicious Tor nodes can insecurely damage or alter the content passing through them and inject malware into the connection. This is one reason why the Electronic Frontier Foundation and the Tor Project began the development of HTTPS Everywhere, including in the Tor browser.