Bar and pie charts are graphical techniques for nominal data.The former focus the attention on the frequency of the occurrences of each category,and the later emphasizes the proportion of occurrences of each category.

Bar Charts

Graphical representations of data using bars of different lengths or heights to compare values across categories.

Pie Charts

A type of graph in which a circle is divided into sectors that each represent a proportion of the whole.

Nominal Data

Data classified into categories that cannot be ordered or ranked, used for labeling variables without a quantitative value.