A Digital Certificate is an electronic document used to prove the ownership of a public key. It contains information about the key, the identity of its owner, and the digital signature of a trusted authority known as a Certificate Authority (CA). This helps ensure that the public key belongs to the person or organization it claims to represent. Digital certificates are essential for secure online communications, such as those used in SSL/TLS protocols for websites. They help establish trust between users and services by verifying identities, enabling secure transactions, and protecting sensitive information from unauthorized access.