Labels:book | clock | hakham | sky OCR: 220 SECTION D CHAPTER 4 Each of your disks contains its own index file so that information about its contents is always available when the disk S in use. Unfortunately, stor- ing this crucial file on disk also presents risk because if the index file is damaged by hard disk head crash or corrupted by a virus, gener- ally lose access to all the data stored on the disk Index files become damaged all too frequently so it is important to back up your data When you save a file, your PC's operating system looks at the index file to see which clusters are empty. It selects one of these empty clusters, records the file data there, and then revises the index file to include the new file name and its location. Afile that does not fit into single cluster spills over into the next contiguous FIGURE 4-4 ...
