What is Certificate Authority (CA)?

A certificate authority (CA) is a third-party entity that issues certificates and manages the public keys required to cryptographically verify digital certificates online. CAs play a critical role in securing much of the information that is exchanged on the internet, and they can be government-based or large multinational corporations. Digital certificates are often used to encrypt digital transactions and identity data to enable the secure exchange of information online. Certificates based on the Transport Layer Security (TLS) protocol and the Secure Sockets Layer (SSL) protocol allow users to securely send instant messages and emails.