What is the purpose of the 'chmod' command in Linux?

The purpose of the 'chmod' command in Linux is to change file permissions. In the Linux file system, every file and directory has associated permissions that dictate who can read, write, or execute them. The 'chmod' command allows users to modify these permissions by specifying the desired access levels for the owner, group, and others. This is crucial for system security and proper file sharing among users, as it determines how files can be accessed and utilized.

Using 'chmod', you can set permissions using either symbolic notation (such as r, w, and x for read, write, and execute respectively) or numeric notation (such as 755 or 644) to represent the permissions succinctly. Hence, 'chmod' is an essential command for managing security and access control on a Linux system.