D3.js, or D3, is a compelling framework in web development. It is an open-source JavaScript library that is used for manipulating documents based on data. It produces dynamic visualisations of data for the web. D3.js provides the building blocks for displaying data through colourful charts, graphs, and maps – instead of boring text and spreadsheets.
D3 takes data that you provide, usually through an external file, and helps to bring that data to life using HTML, CSS, and SVG (Scalable Vector Graphic). D3 is based on web standards which means it will run on all modern browsers without any strings attached. This allows you the ability to generate spectacular visual illustrations with your data.
The entire D3 project is open source and available on GitHub. D3 works with data and web pages as follows:
- Loads the data
- Binds the data to elements.
- Transform the data to a visual output
- Transitions elements based upon triggered events
What does D3.js stand for?
The “D3” part of D3.js stands for “Data-Driven Documents”. The “.js” part stands for “JavaScript”.
What is D3.js used for?
D3.js helps you attach your data to DOM (Document Object Model) elements. Then you can use CSS, HTML, and/or SVG (scalable vector graphics) to showcase this data. You can also make the data interactive through the use of D3.js data-driven transformations and transitions.
How to use D3.js
Using D3 is a process of learning the syntax used to tell it how you want it to load and bind data and transform and transition elements.
The transformation step is most important, as this is where the mapping happens. D3 provides a structure for applying these transformations, using mapping rules that you define. For instance, should larger values make taller bars or brighter circles? Will clusters be sorted on the x-axis by age or category? What colour palette is used to fill in countries on your world map? All of the visual design decisions are up to you. You provide the concept, you craft the rules, and D3 executes it—without telling you what to do.
Where did D3.js come from?
The first web browsers appeared in the early 1990s. In those days, web pages were static – the only way you could interact with a page was through clicking on links and scrolling down pages. One significant change to this was the development of JavaScript, which made it possible to create web pages with rich user interactivity.
Researchers and engineers then began to look at ways to visually present their data on web pages in an engaging format. Multiple projects were attempted to reach this goal, some more successful than others. In 2011, Professor Jeff Heer, PhD student Mike Bostock, and M.S. student Vadim Ogievetsky developed D3.js – a JavaScript library that generated SVG from data while focusing on web standards and improved performance.
Why use D3.js?
D3 allows you to create engaging visuals with charts that move and transform in front of your eyes. Not only is the result fun – but it’s also a way of presenting data so that it’s easier for your audience to understand. Below is a screenshot of what D3 can do on the New York Times’ “How Facebook Compares” analysis of tech company valuations.

It displays a dynamic fluctuation of company value and adjusted worth over the last 30 years. You can view the animation of D3 here.
That’s the beauty of D3.
Advantages
D3 is a fantastic tool used to bind data to a visual representation. And it doesn’t restrict you to a set number of configuration options – there are thousands of ways to visually represent your data through various types of flow charts, graphs, diagrams, and maps.
D3.js is tailored to facilitate animation. You could plot a simple static graph, but why would you when you can visually transform that graph into a moving animation that you can interact with? It is one of the best-supported libraries and is backed by a large and active community. So if you’re having trouble figuring something out with your data chart, chances are good you’ll receive help quickly.
D3.js is not a graphics library, it’s not a data processing library, and there aren’t any pre-built charts that limit your creativity. Instead, it has the tools to make the connection between data and dynamic graphics easy.
Ready to make your data dance?
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