The type of graph to use depends on the type of information.
* line graph: data is continuous for both variables, data are plotted as
points joined by line or curve, useful for showing how changing one
variable affects another
* scatter graph: data is continuous for both variables, data are plotted
as points but not joined, useful for showing if a relationship exists
between 2 variables which cannot be changed
* bar or column graph: discrete data, the height of the bar or column
represents the number of individual items in a particular category, bars do
not touch each other
* histograms: discrete data, the height of the bar or column represents
the number of individual items in a particular class size interval, columns
touch each other because the intervals are continuous
* pie graph: discrete data grouped in categories, circles divided up into
segments, the area of each representing the % of individuals which are in
the categories.
