A Bar Graph is considered as a popular form of Chart. It presents data through rectangular bars. The lengths of the rectangular bars equal to, and are proportional to, the values in the raw data they represent. Bar Graphs can be presented horizontally or vertically.

Since Bar Graphs are "friendly" to the eyes (the "difference" between two variables could easily be understood and spotted in this type of Graph), research results bound to be published publicly are visualized through this form. Students commonly use Bar Graphs to present the data variables in their theses. Non Government Organizations share their recent survey results (usually printed in brochures that are given publicly) through Bar Charts. Bar Charts are also used by the government of many countries to visualize their election results, and/or economic gains and loses.

In statistics, a special type of Bar Chart, called Histogram, is used. A Histogram is a Graphical display of frequencies showed through bars. The difference between a Histogram and an ordinary Bar Chart is that, the area of the bar in Histogram denotes the value, not the height. Distinction is made when variables (presented in "categories") are not uniform in width. In Histogram, the categories (bars) are always adjacent to each other.