Even though this book is primarily about writing applications in PHP, JavaScript has turned into an almost essential tool in a developer's tool belt when building great applications. We've already used JavaScript in our CouchDB views but, in this chapter, we'll use JavaScript for its most common use case-improving our user experience. In order for us to write simpler JavaScript, we're going to use a popular library called jQuery. If you haven't used jQuery before, you are going to be pleasantly surprised at how much it simplifies both common and complex operations in JavaScript.
Luckily, jQuery is incredibly simple to get into any project. We could download it from http://www.jquery.com, but, because we want to focus on speed, we can actually use it without installing anything into our repository.