Introduction

One of the most fundamental tasks that you need to perform with any data visualization project using D3 is selection. Selection helps you target certain visual elements on the page. If you are already familiar with the W3C standardized CSS selector or other similar selector APIs provided by popular JavaScript libraries, such as jQuery and Zepto.js, then you will find yourself right at home with D3's selection API. Don't worry if you haven't used selector API before, this chapter is designed to cover this topic in steps with the help of some very visual recipes; it will cover pretty much all common use cases for your data visualization needs.

Introducing selection: Selector support has been standardized by W3C so all modern web browsers have built-in support for the selector API. However the basic W3C selector API has its limitations when it comes to web development, especially in the data visualization realm. The standard W3C selector API only provides selector...