Which protocol is commonly used for secure data transmission over the internet?

The selection of HTTPS as the answer highlights its role as the secure version of HTTP, which is the foundational protocol for transmitting data over the web. HTTPS, which stands for Hypertext Transfer Protocol Secure, employs encryption protocols such as SSL (Secure Sockets Layer) or TLS (Transport Layer Security) to ensure that the data exchanged between a user's browser and a web server remains confidential and integral.

By encrypting the data during transmission, HTTPS helps protect users from various forms of cyber attacks, including eavesdropping, data tampering, and impersonation. It is widely recognized and mandated for any transactions that involve sensitive information, such as online banking or shopping. The presence of "HTTPS" in a URL also serves as a visual trust signal for users, indicating that they are on a secure connection.

Other protocols such as FTPS (File Transfer Protocol Secure) and SSH (Secure Shell) also facilitate secure data transmission, but they are generally used for different purposes—FTPS for secure file transfers and SSH primarily for secure command line access to remote servers. Thus, their application is more specialized compared to the broader web application of HTTPS.