The Drop Shadow filter simulates the look of an object casting a shadow onto a surface.

For a sample of a drop shadow, see the Flash Samples page at www.adobe.com/go/learn_fl_samples. Download and decompress the Samples zip file and navigate to the Graphics\AnimatedDropShadow directory.
To set the width and height of the drop shadow, drag the Blur X and Y sliders.
To set the distance of the shadow from the object, drag the Distance slider.
To open the Color Picker and set the shadow color, click the color control.
To set the darkness of the shadow, drag the Strength slider. The higher the numerical value, the darker the shadow.
To set the angle of the shadow, enter a value, or click the angle selector and drag the angle dial.
Select Knockout to knock out (or visually hide) the source object and display only the drop shadow on the knockout image.
To apply the shadow within the boundaries of the object, select Inner shadow.
To hide the object and display only its shadow, select Hide Object. Hide Object lets you more easily create a realistic shadow.
Select the quality level for the drop shadow. High is approximate to that of a Gaussian blur. Low maximizes playback performance.