A digital certificate is a certificate of identity issued by an authorized body, the Certification Authority( CA). The certification authority acts as a guarantor. A digital certificate is similar to a digital ID card.
Such certificates are used, for example, in the public key procedure for the secure origin of the public key. This is a digital data structure that reliably binds a public key as part of a key pair to its owner. In addition to the name of the owner and the associated public key, a certificate also contains information about the validity period, the intended use and the publisher of the certificate.
The format for digital certificates is defined in the ITU recommendationX.509 v3.