What role does authorization play in the context of a 403 error?

Authorization is the process of verifying that a user or application has the *right* to access a protected resource, *after* they have been authenticated (proven to be who they say they are). A 403 error indicates that the authentication was successful (the server knows who you are), but authorization failed (you don't have permission to see or access the resource). Authorization checks are typically performed after successful authentication.