Columnar and line charts (histograms)
The classical charts are columnar and linear (strip) of the diagram. Also, they are called histograms. Bar chart are mainly used for visual comparison of the statistical data or to analyze their changes over time. Building a bar chart is in the image of statistics in the form of vertical rectangles, or three-dimensional rectangular columns. Each bar represents the value of the level of the statistical series. All comparisons are expressed as one unit of measurement, and therefore can not compare the statistics of the process.
Variants of bar graphs are linear (strip) of the diagram. They are distinguished by horizontal bars. Columnar and line diagrams are used interchangeably, they considered statistical indicators can be both vertical and horizontal columns. In both cases the image values of the phenomenon using a single measurement of each rectangle - the height or the length of the column. Therefore, the scope of these two diagrams basically the same.
Bar chart can be displayed and groups (both located on a horizontal axis with different dimension variable characters). Generating surface columnar and line diagrams may represent not only the rectangles, but also squares, triangles, trapezoids, etc.