If you see an icon like this at the top-left of a chart cell
...
it means that a chart has been set up as a ‘Parent chart’. In simple terms, it means that this single chart will filter all other charts on the same category based on what you click on.
In this example, we have 2 charts on the category and the ‘Employee Count & Attrition by Job Role’ chart has been set up as a Parent chart. The second chart on the category shows how many employees work in each department.
...