X.509 certificate

File Format
Name	X.509 certificate
Ontology	Electronic File Formats Security X.509 certificate
Extension(s)	.crt
MIME Type(s)	application/x-x509-ca-cert

Certificate Files supply the public key of somebody you wish to communicate with securely, such as a client or vendor. They are used in electronic transaction processing, for instance. You may need to install a vendor's certificate file on your system in order to send transactions such as credit card sales to be processed.

Sample files

• CyberSource certificate

References

• Public-key cryptography (Wikipedia)
• Info on certificate files at CyberSource site