Check Disk

What Does Check Disk Mean?

Check Disk is a system tool provided in Windows, OS/2 and DOS
to verify the file system integrity of a volume as well as for fixing logical
file errors. Similar to the fsck command in UNIX, it also helps in checking
damaged sectors in a physical disk and recovers data from them.


Techopedia Explains Check Disk

For the Check Disk tool to be used, the autochk.exe file needs to be
present in the computer system. In most operating systems, admins have the
options for what switches to execute with the Check Disk command. The main
functionality of Check Disk is to ensure the system or administrative
information regarding files, folders and similar data stored in a physical disk is
correct. Most operating systems are designed to ensure this information is
correct from start to shutdown of the computer. However, improper shutdown of the machine,
removal of USB devices without safely removing them as well as malware or hardware errors
could cause this information to be corrupted. In such cases, Check Disk steps
in to sort out the errors and fix them. It performs an analysis and repairs
errors on disks which are not in use. For
disks which are in use, such as the C: drive in most Windows operating systems,
Check Disk provides a prompt asking for permission to schedule the procedure for the
next time the system is restarted. If the answer is Yes, the Check Disk is
performed at the start of the next system run.

One of the many methods by which
Check Disk locates errors is by making use of a volume bitmap with the disk
sectors allocated to files. However, Check Disk is incapable of repairing
corrupted data which appear to be structurally intact. If the /r command is used with Check Disk, it looks for and recovers any readable data in the disk’s bad sectors. If the /f command is
used with Check Disk, it fixes any errors it finds.


Related Terms

Margaret Rouse

Margaret is an award-winning technical writer and teacher known for her ability to explain complex technical subjects to a non-technical business audience. Over the past twenty years, her IT definitions have been published by Que in an encyclopedia of technology terms and cited in articles by the New York Times, Time Magazine, USA Today, ZDNet, PC Magazine, and Discovery Magazine. She joined Techopedia in 2011. Margaret's idea of a fun day is helping IT and business professionals learn to speak each other’s highly specialized languages.