The htmlwidgets package allows package developers to very easily produce bindings between JavaScript visualization libraries and R. If you wish to make use of the htmlwidgets package to produce a binding to your own favorite JavaScript library, it is a relatively simple process, the details of which can be found at htmlwidgets.org/develop_intro.html. We will not look at the process of producing your own bindings because many popular libraries are available, and there are plenty in this chapter that demonstrate the use of existing libraries. Moreover, it requires competence with JavaScript, which is not assumed in this book. Suffice to say that the htmlwidgets package makes it easy to use JavaScript visualization libraries from R, including R Markdown documents and Shiny applications.

We've already seen leaflet in this book. This package makes use of the htmlwidgets package. In this chapter, we will have a look at some other useful packages that make use of htmlwidgets. For the sake of space, we will look only at the functionality and some example applications, rather than going through all of the code. The application pictured is the one used in the previous edition of this book and all the code for this chapter can be found at chrisbeeley.net/website/shinybookV2.html. 

We will look at the following:

• dygraphs
• rCharts
• d3heatmap
• threejs