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Commonly confused · Systems & Data Center

chmod vs chown: What's the Difference?

chmod changes a file's permission bits, controlling what the owner, group, and others can read, write, or execute. chown changes who owns the file, setting the user owner and optionally the group owner.

chmodchown
ChangesPermissions (mode)Ownership (user and group)
Syntax examplechmod 750 script.sh or chmod u+x script.shchown alice:devs report.txt
NotationOctal (e.g. 644) or symbolic (u, g, o, a with +, -, =)user, user:group, or :group
Who can run itFile owner or rootRoot (regular users cannot give files away)
Recursive flag-R-R
Related commandumask sets default permissionschgrp changes group only
Remember it

chmod changes the mode; chown changes the owner.

Exam tip

Octal conversion is heavily tested: r=4, w=2, x=1, so 754 means rwx for owner, r-x for group, r-- for others. Special bits (SUID 4, SGID 2, sticky 1) may appear as a leading fourth digit.

Tested on

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