Safe/unsafe HTTP methods

HTTP methods can be both safe or unsafe. By safe, it means the methods are not expected to change any resource on the server and by unsafe it means the methods are expected to change some resource on the server. So this way, we have GET as the only safe method, as it is not expected to change anything on the server while other methods such as PUT, POST, PATCH, and DELETE are considered as unsafe methods since they are expected to do some changes on the server.