tools.ietf.org/html/rfc6749#section-4.4
The Client Credentials grant type is used by clients to obtain an access token outside of the context of a user.
This is typically used by clients to access resources about themselves rather than to access a user's resources.
More resources
- Client Credentials (oauth.com)
- Application Access (aaronparecki.com)
- Secure a Node API with OAuth 2.0 Client Credentials (developer.okta.com)