Chart annotations are crucial in data-driven storytelling. They help chart authors to explain and highlight the core messages of their visualisations. As former graphics editor of the New York Times Amanda Cox stated in a now famous quote:
“The annotation layer is the most important thing we do… otherwise it’s a case of here it is, you go figure it out”
In the annotation layer, text annotations are very common, and they are important in explaining patterns in a visualisation. But non-text annotations also exist, and can help in getting the message of your visualisation to your audience. They fall apart into 3 categories:
- Visual annotations: highlights
- Visual annotations: aggregation and distribution
- Visual annotations: icons and images