2.15: Pie Chart
A pie chart (or a pie graph) is a circular graphical chart or a pictorial representation of categorical data. It is divided into slices of pie each indicating numerical proportions. It is also used to show the relative sizes of data in a single chart.
In a pie chart, the central angle, the arc length of each slice, and the area are directly proportional to the quantity or percentage it represents. Some real-world examples that can be depicted using pie charts include marks obtained by students in a class, the monthly expenditure of a family, and the cost of construction of a house. With the help of a pie chart, one can easily compare the sum spent on steel, cement, and so on during construction. The actual sum spent on each individual expense can also be computed.
A pie chart's main advantages are that it is simple to use and easy for the audience to quickly analyze and understand information. However, if there is a lot of data, it may become challenging for readers to visualize and assimilate information using a pie chart.