What protocol is commonly used for secure communications on the internet?

Secure Sockets Layer (SSL) and its successor, Transport Layer Security (TLS), are the protocols specifically designed to provide secure communications over the internet. They work by encrypting data transmitted between clients and servers, ensuring confidentiality and integrity during communication. This encryption helps protect sensitive information such as login credentials, credit card numbers, and personal data from being intercepted by malicious actors.

SSL/TLS protocols are used extensively in various internet communications, including secure web browsing (HTTPS), secure email transfer, and secure file transfers. They authenticate the parties involved in the communication to prevent man-in-the-middle attacks and provide assurance that the data has not been altered during transmission.

In contrast, other options like Hypertext Transfer Protocol (HTTP) transmits data in plaintext without encryption, making it vulnerable to eavesdropping. File Transfer Protocol (FTP) also lacks security measures and transmits data unencrypted. Simple Mail Transfer Protocol (SMTP) is primarily used for sending emails but does not provide inherent security features unless used in conjunction with SSL/TLS. Thus, SSL and TLS stand out as the correct answer for secure communications over the internet.