The main difference between the simple graph and double bar graph is that double bar graphs are used when data has two different sets of frequencies. Double bar graphs are used to compare both data groups and data in between the data set. The main difference is the form of representation. A bar graph is represented by one bar whereas double bar graph is represented by two bars. Both of them are quite easy to plot and give quick analysis for data interpretation.

A bar graph has an axis and also has a series of labels, horizontal or vertical. These series are labeled and each bar whether horizontal or vertical represents a different value. The value of the graph represents some information about an item. Bar graph and Double bar graph are different only based on the fact that the double bar graph shows 2 different kinds of information about the same element. This information can be distinguished in a way that the bars have different colors.

A bar graph represents data using one bar, a double bar graph represents data using 2 bars.

Double bar graphs compare two things over a certain period of time, single bar graphs show change of one thing over a period of time.

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