What is the purpose of the 'chmod' command?

The 'chmod' command is used to change file permissions in a Unix-like operating system. Permissions control the level of access that users and groups have to files and directories. This command allows the user to specify who (the owner, the group, or others) can read, write, or execute a file. By using different modes, such as symbolic or numeric representations, users can modify these permissions as needed.

Understanding file permissions is crucial for security and functionality. For example, a file can be made executable for a specific user or a group, or write access can be restricted to prevent unauthorized modifications. The ability to alter these permissions is an essential part of managing access control within a system.