How do you change file permissions in Linux?

Changing file permissions in Linux is accomplished using the chmod command. This command allows users to modify the access permissions of files and directories. With chmod, you can specify which users (owner, group, others) have the ability to read, write, or execute a file or directory.

The chmod command can be used in symbolic or numeric modes. In symbolic mode, users can add or remove permissions using letters (r for read, w for write, and x for execute), while in numeric mode, users can specify permissions with octal numbers (for example, 755 grants full permissions to the owner, and read and execute permissions to the group and others).

The other commands mentioned serve different purposes: mv is used to move or rename files, cp is for copying files, and ls is for listing directory contents. These commands do not have the capability to alter file permissions, which is why they are not appropriate for this task.