Secure Sockets Layer (SSL) is the technology responsible for data authentication and encryption for internet connections. It encrypts data being sent over the internet between two systems (commonly between a server and a client) so that it remains private. And with the growing importance of online privacy, an SSL port is something you should get familiar with.
Because data can be sent with or without the use of SSL, one way to indicate a secure connection is by the port number. By default, HTTPS connections use TCP port 443. HTTP, the unsecure protocol, uses port 80.
HTTP is not a separate protocol from HTTPS. Rather, HTTPS works by establishing a secure HTTP connection using SSL. Hence, the protocol stacks for HTTP and HTTPS look similar:
