Hard drives don't last forever. In fact, they fail more often than you might think. If your hard drive has ever crashed, you know the hassle it can cause.
But you may be able to get early warning of impending drive failure. These days, many hard drives feature S.M.A.R.T. (Self-Monitoring Analysis and Reporting Technology).
On its own, S.M.A.R.T. won't help you. But software can use this information to keep you updated on your hard drive's health.
HD Tune will warn you of errors that could signal the end of your hard drive. And it will help you keep an eye on your drive's temperature.
An early warning is nice. But don't rely solely on this software. You should still perform regular backups of your data.