In this lesson, students learned about pie charts, which are circular graphs divided into slices to show parts of a whole. Each slice represents a category and its size shows how much it contributes to the total. Pie charts are useful for comparing percentages or fractions, such as budget spending or favorite sports. Key features include a circle shape, labeled sectors, a title, and colors for clear understanding. Unlike line graphs that show change over time, pie charts are best for showing how data is divided into different parts of a whole.