| Number | Binary | Symbol | Permission Description |
|---|---|---|---|
| 0 | 000 | --- | No Permission |
| 1 | 001 | --x | Execute Only |
| 2 | 010 | -w- | Write Only |
| 3 | 011 | -wx | Write + Execute |
| 4 | 100 | r-- | Read Only |
| 5 | 101 | r-x | Read + Execute |
| 6 | 110 | rw- | Read + Write |
| 7 | 111 | rwx | Full Permissions (Read + Write + Execute) |
Chmod (Change Mode) is a command in Unix and Linux systems used to change file or directory access permissions. Permissions are divided into three groups: Owner, Group, and Others, each with three types of permissions: Read (r=4), Write (w=2), Execute (x=1).
chmod 755 filename Set the file to full permissions for the owner, and read and execute permissions for others.