What provides descriptive text for the individual data markers such as pie slices?

Descriptive text for individual data markers, like pie slices in a chart, is typically provided through tooltips or labels. Tooltips appear when a user hovers over a specific marker, displaying relevant information such as the value or percentage represented by that segment. Labels can be directly placed on or near the markers, showing key data points without user interaction. Both methods enhance data comprehension and visualization clarity.