418: I'm a teapot

HTTP Status Code 418 refers to I'm a teapot. This is an April Fools' joke status code defined in RFC 2324, which was published in 1998. The code indicates that the server is a teapot and therefore cannot brew coffee. The humorous nature of this status code is not intended for actual use in production systems; instead, it serves as a light-hearted reminder that not all status codes need to be serious.

417: Expectation Failed

HTTP Status Code 417 refers to Expectation Failed. This status code indicates that the server cannot meet the requirements of the Expect request-header field sent by the client. When a client sends a request with this header, it is essentially asking the server if it can fulfill certain expectations for the response.

415: Unsupported Media Type

HTTP Status Code 415 indicates Unsupported Media Type. This status is returned when the server refuses to accept the request because the payload format is in a format that is not supported by the server for the requested resource. For instance, if a client attempts to upload a file with a media type that the server cannot process, such as sending a JSON payload to an endpoint that only accepts XML, the server will respond with this status code.

414: URI Too Long

HTTP Status Code 414 signifies URI Too Long. This status is returned when the server refuses to process a request because the length of the URI exceeds the server's limit. A client might encounter this response when the request includes a long query string or overly long URL, which can happen during complex searches or when sending large amounts of data in the URL. In response, clients should consider shortening the URI, possibly by using POST instead of GET to send data in the body rather than the URL.

413: Payload Too Large

HTTP Status Code 413 indicates Payload Too Large. This status is returned when the server refuses to process a request because the request payload is larger than the server is willing or able to process. Essentially, it informs the client that the submitted data exceeds the size limits set by the server, which may be due to server configuration or resource constraints. Clients receiving this response should consider reducing the size of the request payload before retrying.

412: Precondition Failed

HTTP Status Code 412 signifies Precondition Failed. This status is returned when a client makes a request that includes certain conditions in the If-Match, If-None-Match, If-Modified-Since, or If-Unmodified-Since headers, but those conditions are not met by the server. Essentially, the server is informing the client that the request cannot proceed because the specified conditions regarding the resource's state are not satisfied.

411: Length Required

HTTP Status Code 411 indicates Length Required. This status is returned when the server refuses to accept a request without a defined Content-Length header. When a client sends a request that requires a body, like a POST or PUT, the server expects the client to specify the size of that body. If the client fails to include the Content-Length header, the server will respond with a 411 status, signaling that the request cannot be processed until the required information is provided.