Multiple Bar Graph

A multiple bar graph contains comparisons of two or more categories or bars.  One axis represents a quantity and the other axis identifies a specific feature about the categories.   Reading a multiple bar graph includes looking at extremes (tallest/longest vs. shortest) in each grouping.  The first example is a vertical multiple bar graph.

This sample contains a key that explain the colors for the categories; no practice and 12 hours practice.
The y axis identifies the number (quantity) of misses.
The categories are compared by age in hours.
The example to the right is a horizontal multiple bar graph.
This sample contains a key that identifies the categories; countries or regions in the world.
The x axis represents the quantities; thousands of quads of natural gas.
The categories are compared by resources in each country or geographic region by amount of quads.