Whenever I try to understand anything about SSL I always have a hard time keeping track of what "key" and "certificate" refer to. I fear many people use them incorrectly or interchangeably. Is there a standard difference between a key and a certificate?
The difference between a certificate and a key with respect to SSL
A certificate contains a public key.
The certificate, in addition to containing the public key, contains additional information such as issuer, what the certificate is supposed to be used for, and other types of metadata.
Typically, a certificate is itself signed by a certificate authority (CA) using CA's private key. This verifies the authenticity of the certificate.