Scandisk is an MS-DOS utility that is incorporated into the Windows 95 operating system. To run Scandisk, you can click the Start Button, then choose Run, and then type in the word "Scandisk" (without the quotes). Clicking OK will bring up a dialogue box similar to the one shown below.
Clicking Start will tell the computer to take a look at your Hard Disk and test it for physical imperfections and data errors. The scan can be done in Standard mode or Thorough mode and can be instructed to Automatically fix errors. This utility very useful in maintaining a healthy hard drive.