Ever use an Excel file (workbook) with multiple worksheets and need to see how a change in one worksheet will affect a formula in a different worksheet within the same file? You can use the New Window feature in the View Menu to open a second window for your document. This allows you to "work in different places at the same time." If you have two monitors it is really nice. You can have a different worksheet on each monitor to easily see how a change on one affects the other!