It is a very well known fact that your hard drive is the most likely device on your computer to fail. A hard drive’s life can last anywhere from several hours to several years, but it isn’t a matter of if it will crash, rather when.
One thing you can do to help detect if a drive is in good health is periodically testing it with the respective manufacturer’s diagnostic tools. These can be downloaded for free from each manufacturer’s website, or more conveniently in an all-in-one package inside the Ultimate Boot CD.
For the most part, pretty much all modern hard drives come equipped with SMART detection which basically is the drive alerting the system when something is wrong. While this is usually sufficient, it never hurts to forcefully test your entire drive for any indication of error, which is what the hard drive tools are designed to do.
Keep in mind, even hard drives in tip-top condition are subject to fail at any instant, so having your data backed up is very important.