Sets or returns the chart's type (Area, Column, Bubble, etc.).
The value returned is the ChartType for the chart. This is the chart type that will be used for newly created series if you do not explicitly specify a ChartType in the call to CreateSeries. However, there may be series within the chart that are of a different type than the chart itself - for example, you may have a Line chart with one line series and one column series.
If all of the series in the chart are of the same ChartType, then this property will return that type, and any series created with the SeriesCollection.CreateSeries(string) method will also be of that type. You can create a series that is not of the chart's ChartType by using the SeriesCollection.CreateSeries(string, ChartType, AxisType) method.
Setting the Chart's ChartType will convert every series within the chart to be of the specified type. If the new ChartType supports series on the secondary axis, then the AxisType for each series will be preserved. If the new ChartType does not support series on the secondary axis, such as surface or 3d charts, then all series will be moved to the primary axis.