Chart 
A graphical view of business content to help users analyze and compare data.
A chart consists of:
A category axis (X-axis)
A value axis (Y-axis)
Data series, which are combinations of values on the category axis plotted against values on the value axis

In this example, Number of Activities is the value axis and Results is the category axis.
The Results category axis consists of the values, Successful, Unsuccessful, Rejected by Customer, and Not Available.
Each value on the Results category axis has a corresponding value on the Number of Activities value axis, such as 10 for Rejected by Customer and 27 for Successful. These values form the data series, Activities.