There are three types of timestamps for a GNU/Linux file:
mtime: the modification time (ls -l),
ctime: the status change time (ls -lc), and
atime: the last access time (ls -lu).
Note that ctime is not file creation time.
Overwriting a file will change all of mtime,
ctime, and atime of the file.
Changing permission or owner of a file will change ctime and
atime of the file.
Reading a file will change atime of the file.
Note that even simply reading a file on the Debian system will normally cause a
file write operation to update atime information in the
inode. Mounting a filesystem with the noatime
option will let the system skip this operation and will result in faster file
access for the read. See
touch(1) command to change timestamps of existing files.