Now that you've created a basic worksheet, and you're acquainted with Excel's spiffy interface, it's time to get down and dirty adding data. Whether you want to plan your household budget, build a sales invoice, or graph your soaring (or plunging) net worth, you first need to understand how Excel interprets the information you put in your worksheet.

Depending on what kind of data you type into a cell, Excel classifies it as a date, a number, or a piece of text. In this chapter, you'll learn how Excel makes up its mind and how you can make sure it makes the right decision. You'll also learn how to use Excel's best timesavers, including the indispensable Undo feature and the spell checker. Finally, you'll consider inserting something completely different into your worksheets: a Web-style hyperlink.