When files are deleted or the hard drive is formatted, which part is primarily affected?

The master index is primarily affected when files are deleted or when the hard drive is formatted because it serves as a central reference for the location of files on the disk. When files are deleted, the entries in the master index that correspond to those files are typically marked as available or deleted, but the actual data may remain on the disk until it is overwritten by new data. In the case of formatting the drive, the process generally involves erasing the master index itself, thereby indicating that the drive is empty and ready for new data, although the files can potentially still be recovered until they are overwritten.

The file allocation table, while also important in tracking file storage, has its role primarily in older file systems and may not be as relevant in modern contexts where alternative indexing methods are used. The entire drive is not solely affected in a specific way, as formatting or deleting files does not erase the physical data immediately. Backup copies are not directly impacted by deletion or formatting actions unless specific measures are taken to delete those backups as well.