JavaScript by Example

JavaScript WebAPIs

So far, we have used a few WebAPIs such as FileReader, document (used in the document.querySelector() methods), HTMLImageElement (the new Image() constructor we used in Meme Creator), and so on. They are not part of the JavaScript language, but they are part of the WebAPIs. When running JavaScript in browsers, it will be provided with a window object that contains all the methods of the WebAPIs. The scope of the window object is global and the properties and methods of the window object are also global. This means, if you want to use navigator WebAPI, you can either do the following:

window.navigator.getUserMedia()

Or, you can simply do as follows:

navigator.getUserMedia();

Both will work just fine and implement the same ...