Development ends for Protovis
D3 and Protovis have the same primary author (Mike Bostock), so it’s not surprising that these two systems take a similar approach to visualization. However, there are plenty of important differences, too; enough that it made sense to start anew, rather than patching the design of Protovis. Many of these changes were influenced by observing users’ successes and struggles with past approaches.
D3 and Protovis also share the same goal: to enable you, the web developer (however experienced you may be), to build custom visualizations in the browser with a minimum amount of effort. Not “zero” effort, certainly—but at least to alleviate the repetive burden of common tasks, while retaining the expressiveness needed for custom designs. D3 is not a charting library!
Where D3 and Protovis differ is the type of visualizations they enable (the what), and the method of implementation (the how). While Protovis excels at concise, declarative representations of static scenes, D3 focuses on efficient transformations: scene changes. This makes animation, interaction, complex and dynamic visualizations much easier to implement in D3. Also, by adopting the browser’s native representation (HTML & SVG), D3 better integrates with other web technologies, such as CSS3 and developer tools. Our hope is that this makes D3 not only more powerful, but easier to use.
While it makes sense to take advantage the tools in D3.js, Protovis will continue to work as long as you have the library on your server.
If you're interested in learning Protovis, check out our tutorials.