JavaScript is used in all kinds of places. The most popular way we get introduced to JS is through web browser.
When we view HTML in the browser, the browser turns the HTML into the DOM: Document Object Model. We can see the DOM in the Elements tab in Dev Tools.
We can interact with the DOM like listening for clicks, add/remove elements from the DOM, fetch new data, play music and video etc. using JavaScript.
The window:
- Global scope of browser
- All global variables are stored.
- Helpful properties like
location, innerWidthpresent on window object.
- It is everything about the currently open window including the browser bar, tabs, scrollbars etc.
The document:
- Responsible for everything from
<html>to</html>
- Not concerned with tabs, scrollbar, browser bar etc.
The navigator:
- Higher level than window.
- gives info about the browser and the device that it's on
- things like webcam, audio access, battery level, GPS and other device specific features live on navigator.