I came across this great link which gives a really nice rolling example of what the OSD functions are and how the xml looks.

http://www.tmurgent.com/OSD_Illustrated.aspx 

Its a really good thing to see and play with.

This small tool allows you to explore the xml syntax of the OSD file in an interactive way. Place mouse over items in the OSD file below for a description of the item.

What's an OSD file? Open Software Description: a standard format created by Microsoft as part of an obscure project to database software applications using XML. This format was discovered by Softricity long before their Microsoft relationship began. Softricity used this as a base and extended the DTD to meet their needs. A OSD formatted file is now used by SoftGrid as the shortcut description to a SoftGrid client on how to access a SoftGrid enabled application. These files use names that end in ".OSD" as the extension. In addition to this tool you may be interested in the updated SoftGridOSD Schema file in the Tools section of the website.

Check this link below out!

http://www.tmurgent.com/OSD_Illustrated.aspx