In Linux, timestamp is actually stored in the form of number and not in date and time format. So, to make it human readable format Linux convert it into required format of date and time.  Generally, timestamp is recorded for time when any action is performed on file.  It helps to keep records of when a file was accessed, modified or added.   mtime:- Stands for Modification time. It indicates the last time the content of file was modified.  For example- if new data is added, deleted or edited, the modified timestamp changes   To view the modified timestamp, we can use below command:  $ ls - l   ctime:- Stands for change time. It refers to the change in the file property and indicate last time when some Metadata of file was changed.   Example- if permission of file were modified by user or by some automated code, ctime will show the same.  To view the modified timestamp, we can use below command:  $ ls - lc   atime:- Stands for access time. It refers to timestamp when file' content is read by application or user using grep or cat command but did not necessary modify anything in file.  To view the modified timestamp, we can use below command:  $ ls - lu