Several years ago, I posted an online tutorial explaining how Joins work in D3. I used that tutorial to instruct students in my Visual Analytics course at UNC and the tutorial receieved a good amoutn of traffic from the general public as well.
Over the years, however, much about D3 has changed as the library has been improved and extended in new ways. Over the past few semesters, I’ve been buidling up a new and expanded set of up-to-date tutorials and D3 examples for my students.
While there are a variety of Javascript libraries available for creating visualizations, the most widely used is D3.js.
D3 stands for Data-Driven Documents, and at the core of D3 is a programming model in which users join data elements to document elements. These are often SVG elements, but D3 can really be used for any kind of data-driven DOM manipulation. I instruct my students on the basics of D3.js as part of the Visual Analytics course which I teach every fall.