API authentication is a combination of technology and process that proves or verifies the identities of users who want access to an API. Specifically, API authentication involves the use of a software protocol to verify that users are who they claim to be when a client makes an API call. API authentication solutions are usually set up to block access to an API if they detect something wrong with the user’s identity during the API call. It’s online verification of ID, a gatekeeping countermeasure that defends APIs from access by malicious actors. Remember, too, that in many cases, the API user is a machine, not a person.

To learn more about API Authentication, check out this article on the Noname Academy: https://nonamesecurity.com/learn/what-is-api-authentication/