javascript - What does Asynchronous means in Ajax?

Question

What does Asynchronous means in Ajax? and also how does Ajax know when to pull data without server polling?

question from:https://stackoverflow.com/questions/3393751/what-does-asynchronous-means-in-ajax

Answer 1

Asynchronous means that the script will send a request to the server, and continue it's execution without waiting for the reply. As soon as reply is received a browser event is fired, which in turn allows the script to execute associated actions.

Ajax knows when to pull data from server, because you tell it when to do it.