The Public-Key Cryptography Standards are specifications produced by RSA Laboratories in cooperation with secure systems developers worldwide for the purpose of accelerating the deployment of public-key cryptography. In other words we use these standards when we work with public key cryptography in general and especially with digital certificates.

PKCS #1: RSA Cryptography Standard
PKCS #3: Diffie-Hellman Key Agreement Standard
PKCS #5: Password-Based Cryptography Standard
PKCS #6: Extended-Certificate Syntax Standard
PKCS #7: Cryptographic Message Syntax Standard
PKCS #8: Private-Key Information Syntax Standard
PKCS #9: Selected Attribute Types
PKCS #10: Certification Request Syntax Standard
PKCS #11: Cryptographic Token Interface Standard
PKCS #12: Personal Information Exchange Syntax Standard
PKCS #13: Elliptic Curve Cryptography Standard
PKCS #15: Cryptographic Token Information Format Standard

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