In this chapter, we explored several advanced Chart.js topics that you may rarely need, but give you more control over the look and feel of your charts, allowing a high degree of customization and the possibility of integrating it with standard web technologies and frameworks.

We learned how to configure tooltip and legend presentation and behavior using native Canvas options and custom HTML extensions, and how to create pages with multiple charts, mixed charts, and overlaying charts with other graphics using Canvas. We also wrote extensions for Chart.js using its programming API to generate a PNG version of a chart, and to create a simple plugin that adds a background image to a chart.