Imagine losing all of your customer records, all of your spreadsheets and all of your financial data. What would happen to your business if you suddenly had no record of who owed you money? The more you think about it, the easier it becomes to identify the documents you must have in order to run your business.

As we do more business by computer, increasing amounts of our most important data is available only in digital form. All of those ones and zeros are surprisingly delicate — if your hard drive fails, or if a power surge fries your computer or network, that data could be gone forever. Computer viruses are another threat; as a series of recent virus attacks demonstrated, disaster can strike even the most careful computer users.

Fortunately, there's a way to guarantee that you never face a data-loss disaster. When you back up your files, you guarantee that there will always be extra copies of your documents available in case the originals are destroyed. There are many different ways to back up your files, including online services, CD-Rs and DVD-Rs, networks, and external hard drives. What matters most is that you develop and follow a backup plan — it could be the most important business decision you make.