HTTP defines a set of request methods to indicate the purpose of the request and what is expected if the request is successful. Although they can also be nouns, these request methods are sometimes referred to as HTTP verbs. Each request method has its own semantics, but some characteristics are shared across multiple methods, specifically request methods can be safe, idempotent, or cacheable.
GETThe GET method requests a representation of the specified resource. Requests using GET should only retrieve data and should not contain a request content.
HEADThe HEAD method asks for a response identical to a GET request, but without a response body.
POSTThe POST method submits an entity to the specified resource, often causing a change in state or side effects on the server.
PUTThe PUT method replaces all current representations of the target resource with the request content.
DELETEThe DELETE method deletes the specified resource.
CONNECTThe CONNECT method establishes a tunnel to the server identified by the target resource.
OPTIONSThe OPTIONS method describes the communication options for the target resource.
TRACEThe TRACE method performs a message loop-back test along the path to the target resource.
PATCHThe PATCH method applies partial modifications to a resource.
Safe, idempotent, and cacheable request methods
The following table lists HTTP request methods and their categorization in terms of safety, cacheability, and idempotency.
* POST and PATCH are cacheable when responses explicitly include freshness information and a matching Content-Location header.
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