Test your understanding of HTTP protocol fundamentals and common HTTP status codes. This quiz assesses essential knowledge of how HTTP works, key request methods, and the meanings of status codes for web communication.
What is the primary function of the HTTP protocol in web communication?
Explanation: HTTP is designed to facilitate the transfer of data such as webpages, images, and files between clients and servers over the internet. Unlike protocols focused on encryption, HTTP does not encrypt data by default—that is a feature of HTTPS. Managing login credentials is handled at higher layers or through specific authentication methods, not by HTTP itself. Establishing physical network connections is outside the scope of HTTP and is done by lower-level protocols like TCP.
What does the HTTP status code 200 OK represent after sending a GET request?
Explanation: A 200 OK status code indicates the server has successfully processed the client's request and the response contains the requested data. 'Not authorized' is denoted by 401 Unauthorized, 'resource not found' by 404 Not Found, and server errors are represented by 500 Internal Server Error. Only 200 OK confirms a successful request.
If a web server returns an HTTP 404 status code, what has occurred?
Explanation: The 404 status code indicates that the server cannot find the resource specified by the client. A timeout would result in a different error, such as 408 Request Timeout. A malformed request is signaled by 400 Bad Request, while access being forbidden is represented by 403 Forbidden.
When should the HTTP GET method be used in web applications?
Explanation: The GET method is used to request data from the server without causing any side effects or changes. Sending data securely for authentication is more suitable for POST methods over secure channels. File uploads typically use POST, and deleting resources is done with the DELETE method—not GET.
If a resource has permanently moved to a new URL, which status code will the server return?
Explanation: 301 Moved Permanently tells clients that the resource has been permanently moved and provides the new URL. 307 indicates a temporary redirect, while 403 and 500 relate to permissions and server errors, not resource location changes. Only 301 signals a permanent move.
Which HTTP method is considered both safe and idempotent?
Explanation: GET requests are both safe (they don’t modify server data) and idempotent (making the same request repeatedly has the same effect). POST is not idempotent nor safe as it can create or change resources. CONNECT is used for tunnels and is not safe. PATCH modifies resources and is not always idempotent.
What is the main role of headers in an HTTP request or response?
Explanation: HTTP headers relay metadata like content type, language, and message length, helping both client and server interpret the message. While cookies are sent through headers, storing them on the client is not the only role of headers. Headers do not define styles or execute scripts; those functions belong to other technologies.
HTTP status codes in the 400 to 499 range generally indicate what type of error?
Explanation: Codes in the 400–499 range signify errors from the client side, like invalid requests or unauthorized access. Server errors are in the 500s, informational responses in the 100s, and redirection codes occupy the 300s. Only client errors belong to the 400 range.
What does an HTTP 500 Internal Server Error indicate?
Explanation: A 500 error means something went wrong on the server side, preventing successful completion of the request. Invalid credentials would result in a 401 error. A temporary move is a 302 or 307, while success is marked by 200, not 500.
If a user receives a 403 Forbidden error, what does this indicate?
Explanation: A 403 error means the server has understood the request but is intentionally refusing to allow access. Non-existent resources are reported as 404. Unsupported methods might yield a 405 error, and timeouts are communicated by 408 status codes.
Which HTTP status code is typically returned when a resource is successfully created, such as after submitting a form?
Explanation: 201 Created signifies that a new resource has been successfully created, often after a POST operation. 202 means the request is accepted but not completed, 204 marks success without content, and 410 indicates a resource that was deleted and is no longer available.
Which of the following is a valid version identifier in an HTTP request line?
Explanation: HTTP/1.1 is the correct and standardized way to indicate the protocol version. The other options contain typographical errors or use incorrect formats, such as extra 'T's, use of 'HTTPS', or dashes instead of slashes.
In what situation is the HTTP POST method typically used?
Explanation: POST is preferred for sending data like form submissions to the server for processing. Fetching images or static pages should use GET, while deleting is handled by the DELETE method. POST is specifically appropriate for transmitting data that may change server state.
Which HTTP status code most commonly indicates that the client's cached version of a resource is still valid?
Explanation: 304 Not Modified tells the client its stored (cached) copy of the resource is still up to date and there's no need to resend the data. 302 is a redirect, 400 signals a bad request, and 503 denotes server unavailability. Only 304 references caching behavior.
Which status code might a server use to indicate a temporary relocation of a resource to a different URL?
Explanation: 302 Found is used for temporary redirects, instructing the client to fetch the resource from another URL for now. 401 relates to authentication, 204 signifies successful requests without a body, and 451 denotes legal restrictions rather than redirects.
After establishing a connection and sending a basic HTTP request, which status code means the request was received, understood, and is being processed?
Explanation: 100 Continue is an informational status indicating the server has received the request headers and the client should proceed. 418 is a playful, non-standard code, 404 signifies that a resource is missing, and 301 handles redirects, not initial connection acknowledgment.