Secure Sockets Layer (SSL) is a cryptographic protocol designed to provide secure communication over the Internet. SSL provides a secure channel between two communicating endpoints, typically a client (such as a web browser) and a server (such as a website).
The SSL protocol ensures that data exchanged between the client and server is encrypted and protected from unauthorized access, interception, or tampering. SSL uses a combination of symmetric and asymmetric encryption algorithms to establish a secure connection between the two endpoints.
SSL works by performing a "handshake" between the client and server. During the handshake, the client and server agree on a set of encryption algorithms and exchange encryption keys. Once the handshake is complete, the client and server can communicate securely using the agreed-upon encryption algorithms.
SSL is commonly used to secure online transactions, such as credit card payments, online banking, and e-commerce. It is also used to secure sensitive data transmission such as emails and login credentials. SSL has been widely adopted and has been superseded by the newer TLS (Transport Layer Security) protocol, although the term SSL is still commonly used to refer to both SSL and TLS.