Principle of jsonp

It is indispensable to deal with ajax in the work. To avoid making more wheels, normally we just use the ajax function of jQuery. Ajax in the same origin is known to use the xhr (XMLHttpRequest) requests. In jquery, jsonp requests are also called ajax, only the parameters are different, but in fact, cross-domain jsonp request is actually a fundamentally different concept, jsonp does not use xhr request at all ...