What does document and window mean in JQuery?

Answer 1

jQuery is a library that leverages JavaScript native functionality. Basically, jQuery makes it easier to develop because it provides out-of-the-box methods that perform common functionality on the client side (instead of developers writing those methods themselves, some of which could be very time consuming). That means that under the hood everything in jQuery is simply JavaScript. The "document" and "window" objects are no different: they native Javascript objects (part of the language specification), not jQuery.

You can read up on those on the MOZ docs:

https://developer.mozilla.org/en-US/docs/Web/API/Window

https://developer.mozilla.org/en-US/docs/Web/API/Document