You see the By Person worksheet in the Excel program. The By Person worksheet is not displayed in Excel Services.
Taking this example further, let's say you are the sales manager at Adventure Works, and you would like the following:
You want to see the By Person worksheet in the Excel program, because you'll occasionally need to work with it in Excel.
You want to hide the By Person worksheet in Excel Services, because you don't think it's appropriate for that to be visible to everyone in their Web browsers.
This is possible to do, as the next few pages will explain.