What is the purpose of `root:root`?

In the command sudo chown -R root:root new-dir, the string root:root specifies the new owner and the new group for the files and directories.

Here is the breakdown of the syntax user:group:

1. The first root (User): This specifies the Owner of the file. root is the superuser in Linux who has administrative privileges and can access almost any file on the system.
2. The colon :: This is a separator used by the chown command to distinguish between the user and the group.
3. The second root (Group): This specifies the Group ownership. In Linux, every user usually belongs to a group with the same name. By setting this to root, only members of the root group will have the "group" level permissions defined for that file.

Why do we use it?

• Security: By changing ownership to root:root, you are taking ownership away from a regular user (like labex) and giving it to the system administrator. This prevents regular users from modifying or deleting important files unless they use sudo.
• System Organization: Many system-level configuration files and directories are owned by root:root to ensure that only the operating system or an authorized administrator can manage them.

In summary: root:root means "Set the owner to the root user and the group to the root group."