An ordinary Excel workbook stores a bunch of information, and uses Excel tools (like formulas and charts) to analyze it. However, a great deal of the world's business information isn't stored in Excel files. Instead, it sits inside databases—organized catalogs of information managed by high-powered computer software.

Typical mid-size companies (or bigger ones) store product catalogs, customer lists, and purchase orders in databases. When they need to change this information (or just take a look at it), they use another program that talks to the database. Databases are extremely fast, secure, and durable. They're the best place to put mission-critical information.