A Calendar chart helps to display the data for months or years. This is a good way to compare data over time. They highlight holidays or any important dates. The most granular value of this chart is a day.
Why do you need it?
A Calendar chart helps to show a trend over a long time span. It can help to visualize the whole year and getting insights into important days efficiently and saving-time. In this chart, each month and date are in a chronological order making it attractive and useful.
What kind of data you can visualize with it?
Assume you have to make a holiday calendar for students of a school, then it could be beneficial. The chart could indicate holidays just like a heat map in the chart dates grid. The chart can help students understand which day to go to school and when not.