Basics of Linux file permission

Linux is a multi-user operating system and it uses the concepts of “ownership” and “permissions” to enhance the security of the files and directories.

Every file and directory on Linux system is owned by a specific user and group. Therefore, file/directory permissions are defined separately for users, groups, and others.

User: The username of the person who owns the file/directory. By default, the user who creates the file/directory will become its owner.