What is meaning of xhr.readystate===4

Question

Is it right to say that the AJAX call has completed after xhr.readystate===4?
Here it says the state is complete. So what does th

Answer 1

An Ajax http request has 5 states as your reference documents:

0   UNSENT  open() has not been called yet.
1   OPENED  send() has been called.
2   HEADERS_RECEIVED    send() has been called, and headers and status are available.
3   LOADING Downloading; responseText holds partial data.
4   DONE    The operation is complete.

State 4 means that the request had been sent, the server had finished returning the response and the browser had finished downloading the response content. So, it is right to say that the AJAX call has completed.