Excel's workbooks don't just provide a glimpse at data held in tiny cells on a grid, it will let you view multiple grids of information at a time, essential for comparing and contrasting, such as ...

While there is a way for you to open two Excel workbooks at the same time, you can also open multiple spreadsheets in separate windows. Learn how!

A complex Excel 2007 workbook could require multiple sheets. By default, Microsoft provides three sheets on each workbook, but you can add as many as you need.