Please look in Help. Here is what I did:
Help->Help Topics
In the Type in the keyword to find
sheet metal
You should get a dialog box with
About sheet metal styles
Click on it
and you should see the below under Concept:
A sheet metal part has a number of parameters that describe its characteristics and how it is manufactured. For example, sheet metal has a uniform thickness and the bends usually have the same radius.
The Styles tool specifies default parameters for the part. The material is also available on the Physical tab of the Properties dialog box. When you activate the sheet metal environment, the bend and corner parameters are added to the parameters list and can be used in dimensions and equations. If you switch to the part modeling environment, the bend and corner parameters remain in the parameters list.
When creating individual features you can manually override bend parameters, including unfold options for flat patterns. You can also modify any existing bend on a feature-by-feature basis. To change other parameters for existing sheet metal parts, modify the values in the Parameters dialog box.
You can create new sheet metal parts with parameter values other than those defined by the default style. Create a new style in the Sheet Metal Styles dialog box, and then make it the active style.
Similarly, you can click on the Reference and Procedure tabs and get more information about active styles, etc.
I would encourage you to change the data in the styles and try it out. Thanks
shekar