Ckdisk

I'm unfamiliar with "ckdisk"... did you mean chkdsk?

I'm not sure what you mean by "what&How?" so I will make assumptions.

Open a command prompt window and type in:

chkdsk /?

This will explain how the command works and which switches can be used.

I have bolded it in the italicised example below.

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Microsoft Windows [Version 6.1.7100]
Copyright (c) 2009 Microsoft Corporation. All rights reserved.

C:\Windows\system32>chkdsk /?
Checks a disk and displays a status report.


CHKDSK [volume[[path]filename]]] [/F] [/V] [/R] [/X] [/I] [/C] [/L] [/B]


volume Specifies the drive letter (followed by a colon),
mount point, or volume name.
filename FAT/FAT32 only: Specifies the files to check for fragmentation
.
/F Fixes errors on the disk.
/V On FAT/FAT32: Displays the full path and name of every file
on the disk.
On NTFS: Displays cleanup messages if any.
/R Locates bad sectors and recovers readable information
(implies /F).
/L:size NTFS only: Changes the log file size to the specified number
of kilobytes. If size is not specified, displays current
size.
/X Forces the volume to dismount first if necessary.
All opened handles to the volume would then be invalid
(implies /F).
/I NTFS only: Performs a less vigorous check of index entries.
/C NTFS only: Skips checking of cycles within the folder
structure.
/B NTFS only: Re-evaluates bad clusters on the volume
(implies /R)

The /I or /C switch reduces the amount of time required to run Chkdsk by
skipping certain checks of the volume.

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I hope I didn't take more time trying to answer your question as it took for you to make it

you should at least select him as the best answer, he took his time trying to assume what you wanted to ask.