Bar charts
Although a frequency table itself provides a useful description of a categorical distribution, a graphical display of the frequencies is often easier to absorb. The main graphical display of categorical data is a bar chart.
For each distinct category, a bar is drawn with height equal to the frequency (or equivalently relative frequency) of that category.
Tanzania drinking water
The bar chart below shows the sources of drinking water for rural households in Tanzania.
Clicking on any bar highlights it and the corresponding values on the frequency table.
Note that the bar chart is shown with both a frequency axis (on the left) and a proportion axis (on the right). It has the same shape whichever is used.