Transport Layer Security (TLS) is the successor to Secure Sockets Layer (SSL) and is designed to ensure privacy between communicating applications and users on the internet. It encrypts data transmitted over various types of networks to prevent eavesdropping, tampering, and message forgery. TLS operates between the transport and application layer in the OSI model, making it agnostic to the underlying transport protocol, and can be implemented atop protocols such as HTTP, FTP, or SMTP.