A line chart or also known as line graph is a chart type that is used to display frequencies in data. To do that it connects data points to form a line. The measurement points are typically ordered by their x-axis value and connected through line segments. Line charts are created so that the independent data is on the x-axis (for example time or distance) and the y-axis contains the dependent data. The following example shows the value changes of three data sets over a specific time.
Line charts are mostly used to show trends in data and can help to do predictions or forecasts of data that is not yet recorded. Also they are used to display dependent variables against one specific independent variable or to compare different data sets that are plotted in one line chart. But when it comes to compare data, line charts are only useful of the axes have the same scales. Other purposes of line charts are for example:
To create a good line chart it is necessary to know what the exact purpose of the diagram is. Also the line chart should: