What is the difference between HTTP status codes 200, 201, and 204?

• A. 200 OK returns content; 201 Created indicates a new resource; 204 No Content means success with no body.
• B. 200 OK returns content; 201 Created is an error; 204 No Content means the body is always present.
• C. 200 OK means a redirect; 201 Created indicates a missing resource; 204 No Content means failure.
• D. 200 OK returns content; 201 Created indicates a new resource; 204 No Content means success with no body.

Answer: (D)

Understanding how the 2xx family works helps you read API responses at a glance. A 200 OK means the request succeeded and the response typically includes content—the resource or result you asked for. A 201 Created confirms that a new resource was created as a result of the request; you’ll usually get information about that new resource (often via a Location header with its URL, and sometimes a representation in the body). A 204 No Content means the request succeeded but there is no response body to return; you may still have headers with information, but nothing to display in the body. This set distinguishes whether content is returned and whether a new resource was created, which is why it’s the correct pairing.