A chart or a graph is a pictorial representation of data. Charts and graphs are used to display detailed information and relationships between quantitative data. Examples of charts include bar graphs, pie charts, histograms and time-series graphs.
Charts are often found alongside tables that contain the same data, because people can sometimes make observations and draw conclusions faster through graphical representations than through text. Although charts vary in form, they share common features such as titles, axes for dimensions, grids, labels and legends.
Choosing the correct type of chart helps in presenting data clearly. A bar graph, which consists of rectangular bars whose lengths reflect the values they represent, is appropriate for comparing frequencies of categorical data. A pie chart presents each item as a slice of a circular pie to make composition analysis. A histogram looks similar to a bar graph, but it displays data at the ordinal level of measurement. A time-series graph show changes in data over time.
Charts are more effective when they have accompanying descriptive texts, labels and tips on how to interpret the data. Arranging data in order also helps in finding patterns and trends. Office suite programs, such as word processors, spreadsheets and presentation software, typically offer comprehensive tools for creating charts. Chart and graph generators also are available online.