The PUT method is an HTTP request used to update or create a resource on a server. It sends data to the server, which then processes the request and updates the specified resource with the provided information. This method is idempotent, meaning that multiple identical requests will have the same effect as a single request. In RESTful APIs, PUT is commonly used to modify existing resources or to create new ones at a specific URI. For example, if a user wants to update their profile information, a PUT request can be sent to the server with the new data, ensuring that the resource is accurately updated.