The FFD cyl tool works on the free form. The use of these tools is to stretch the free model.
Step1: Create a sphere and click on modify tab then select FFD cyl tool.
Fig.40
Step2: Click on the flip arrow of the FFD cyl tool. Then select control point option.
Fig.41
Step3: Select scale tool and select some control point.
Fig.42
Step4: After that click on X-axis and drag up or down side.
Fig.43