Which status code indicates the server understood the request but requires authentication to proceed?

Which status code indicates the server understood the request but requires authentication to proceed?

• A. 200
• B. 201
• C. 401
• D. 403

Answer: (C)

When a server can understand what you asked for but wants you to prove who you are before it will proceed, it signals that authentication is required. That specific response is the 401 Unauthorized status. It tells the client to provide valid credentials, often with a WWW-Authenticate header that describes the challenge. This is different from a successful response (200) or a resource creation (201), which indicate the request went through. It’s also distinct from 403 Forbidden, which means you are already authenticated but don’t have permission to access the resource. So, the 401 Unauthorized status is the one that matches “the server understood the request but requires authentication to proceed.”

When a server can understand what you asked for but wants you to prove who you are before it will proceed, it signals that authentication is required. That specific response is the 401 Unauthorized status. It tells the client to provide valid credentials, often with a WWW-Authenticate header that describes the challenge. This is different from a successful response (200) or a resource creation (201), which indicate the request went through. It’s also distinct from 403 Forbidden, which means you are already authenticated but don’t have permission to access the resource. So, the 401 Unauthorized status is the one that matches “the server understood the request but requires authentication to proceed.”