Definition of HTTPS in the Network Encyclopedia.
What is HTTPS?
HTTPS is a protocol developed by Netscape for secure transmission of Web content over the Internet. HTTPS is another name for Netscape’s implementation of the Secure Sockets Layer (SSL) protocol that functions as a subprotocol to the application layer (layer 7) protocol, Hypertext Transfer Protocol (HTTP).
HTTPS is based on the public key cryptography system and allows information transmitted over the Internet to be encrypted for greater security. To run HTTPS on a Web server, you must install a digital certificate on the server. Web browsers will then connect to the server by providing a Uniform Resource Locator (URL) that begins with the prefix https:// rather than http://. The designation “HTTPS” comes from the combination of HTTP and secure.
Difference between HTTP and HTTPS
HTTPS URLs begin with “https://” and use port 443 by default, whereas, HTTP URLs begin with “http://” and use port 80 by default.
»» Read: What is the difference between port 80 and port 443?
HTTP is not encrypted and is vulnerable to man-in-the-middle and eavesdropping attacks, which can let attackers gain access to website accounts and sensitive information, and modify web pages to inject malware or advertisements. HTTPS is designed to withstand such attacks and is considered secure against them (with the exception of older, deprecated versions of SSL).
HTTPS uses the TCP well-known port number 443 instead of port 80, which is used by HTTP. HTTPS is not the same as Secure Hypertext Transfer Protocol (S-HTTP).