Excel 2007 enables you to manage large amounts of numerical data effectively, but humans generally have a hard time determining patterns from that data if all they have to look at are the raw numbers. That's where charts come in. Charts summarize your data visually, which means that you and other decision-makers can quickly detect trends, determine high and low data points, and forecast future prospects using mathematical tools. The Excel charting engine and color palette haven't changed significantly since Excel 97, but Excel 2007 marks a tremendous step forward with more ways to create attractive and informative charts quickly.
For more information on the new charting capabilities in Excel 2007, see Chapter 11, "Creating Charts and Graphics."