A digital certificate means electronic documents issued by a Certification Authority. The digital certificate contains information about who the certificate was issued to, as well as the certifying authority that issued it. These certificates can be issued by trusted parties called Certificate Authority (CA).In a simple way ,it can be said that it is just like an electronic ID card in which all the information regarding ID cardholder is available.

What are Digital Certificates?

Digital Certificate is the best way to prove your identity or your right electronically to access information or services online. The main purpose of digital certificate is online Security and secure data transfer. The most common use of a digital certificate is to authenticate that a user sending a message is who he or she claims to be, and to provide the receiver with the means to encode a message. A Certificate Authority (CA) is a trusted central administrative body that can issue digital certificates to users.

The most important things in Digital certificates are as follows:

- Identification information. - Cryptographic keys. - Digital signature.

Identification Information-

Every CA has a guiding principle to verify what identifying information the CA requires issuing a certificate.

Digital Certificate must contain:

- Name of the organization or individual. - The business address. - Digital signature. - Public key. - Serial number. - Valid Issued date. - Valid Expiration date.

Cryptographic Keys-A digital certificate has a pair of coupled cryptographic keys. These are symmetric and asymmetric cryptographic. Symmetric cryptographic key uses only one key between two parties i.e. encryption and decryption is done by same keys. Asymmetric cryptographic key uses different keys between two parties i.e. encryption and decryption is done by different keys. These keys always work in pairs i.e. one key is public to all which is only for the owner known as public key and private key is distributed to all the users which is always different from one customer to other. The main work of these keys is to encrypt and decrypt the messages and to secure the whole process of transactions.