Graphs are used to present numerical facts in a visual form in order to make it easier to interpret information. Certain graphs display information easier than others depending on the circumstance.

Bar Graph:

Typically used to compare quantities. It is important to use the correct scale so that the information will fit on the diagram. For instance it would not make sense if every number on the left hand side of the graph went up by increments of 1. The graph would be too large. If the scale was too large (increments of 2000), then the bars would not provide any useful information, as they would be too small to compare.

Line Graph:

The most common use for line graphs is to show numerical changes over a period of time.

Pie Graph:

A pie graph is most often a visual representation of a whole quantity divided into parts. The example below is of a company budget. A circle has 360 degrees so to determine the number of degrees each angle should have you should multiply the percentage of the grouping by 360 degrees. For instance the angle for sales would be 33% x 360 = 118.8 degrees.