What is HTTPS?

HTTPS is HTTP within SSL/TLS. TLS establishes a secure tunnel for bidirectional binary data communications between two hosts (the web server and browser). HTTP (Hypertext Transport Text Protocol) is the communications protocol that the client and server use to talk to each other:

So, think of HTTP as water inside a pipe. The pipe is the TLS encryption and the water is the data. The primary difference between HTTPS and the water analogy is that HTTPS is bidirectional and plumbing isn't.

There are other communication protocols that support TLS, such as web sockets (WSS), email (SMTPS), and FTP (FTPS).