The acronym SSL stands for Secure Sockets Layer. It is a standard security protocol designed to establish an encrypted link between a web server and a client's browser, ensuring the secure transmission of data over the internet. It helps protect sensitive information, such as login credentials and payment details, from interception by unauthorized parties. SSL has been largely replaced by TLS (Transport Layer Security) for its enhanced security features, but the term SSL is still commonly used in the context of securing web communications.