In the preceding section, we saw how to schedule JavaScript code to run at a later time. This is done explicitly by other JavaScript code. Most of the time, our code runs in response to user interactions. In this section, we'll look at the common interface that's used not only by DOM events, but also by things such as network and web worker events. We'll also look at a technique for dealing with large volumes of similar events—called debouncing.
The EventTarget interface is used by many browser components, including DOM elements. It's how we dispatch events to elements as well as listen to events and respond by executing a callback function. It's actually a very straightforward interface that's easy to follow. This is crucial since many different types of components use this same interface for event management. We'll see as we progress through the book.
The same task queue mechanisms that execute the callback functions for the timers that we used in the...