5.1.2 When are bar charts used?
A bar chart is a good method of representation if you want to illustrate a set of data in a way that is as easy to understand as it is simple to read. In general, a bar chart should be used for data that can be counted so, for example, we could use a bar chart to show the number of families with 0, 1, 2 or more children. A bar chart could also be used to show how many people in one area use each of the different modes of transport to get to work.
Bar charts are very useful for comparing two or more sets of data, as you will see later. For example, the popularity of different modes of transport in two cities, or from one year to the next.