Glossary
PKCS#11
The Cryptoki standard API for talking to hardware security modules, smart cards and tokens, now maintained by OASIS.
PKCS#11, also called Cryptoki, defines a C API through which applications use cryptographic tokens without knowing their internals. A vendor ships a PKCS#11 module (a shared library); applications load it and work with slots, tokens, sessions and objects such as keys and certificates, using mechanisms like CKM_ECDSA or CKM_AES_GCM.
Originally published by RSA Laboratories, the standard is now maintained by OASIS. It is supported by OpenSSL, Java (SunPKCS11), many PKI and signing tools, and by software implementations such as SoftHSM2 that are useful for development and testing.