In Linux, the super user is a user who has all access permissions to operating system resources, that is, the root user. This permission can be used to maintain and manage the system; the account created by default during system installation is Standard users, only super users can set permissions on the system.
#The operating environment of this tutorial: linux7.3 system, Dell G3 computer.
Super user
1. In the Linux operating system, there is a concept called super user (root): the person who owns the operating system All access rights to resources, used for system maintenance and management (adding or deleting users or groups, installing software, etc. to manage the system).
2. In the Linux operating system, it is not recommended that users log in to the system as a super user in daily use to prevent deletion of important files or folders and other contents, which may cause the system to crash.
3. When installing the Linux operating system, it will help us create an account (created by default). This account created by default is called a standard user (can only access content under the user's permissions, and can only If the operation is performed under the permissions of the user's home directory, important files or folders in the system will not be deleted, because without this permission, the security of the system is guaranteed.)
4. The reason why the standard user uses the root command: because the standard user may perform some system maintenance work (such as creating a user or a group, and these permissions to set the system are only available to the super user root, but if we do not want to log in root authority, so the sudo command was born~~
The role of the super user
In different computer systems, the name of the super user also varies depending on the system. Different depending on the situation, the common ones are root and administrator. In a computer system, generally speaking, the super user has full access rights to all directories and files. It is the first user to log in after installing the operating system. The super user can Create other ordinary users and assign permissions to ordinary users.
Simply put, the computer system is like a feudal kingdom, the super user is the king of the kingdom, and the ordinary users are the ministers and ordinary people in the kingdom , their authority is generally granted directly or indirectly through the king, the super user. In this kingdom, the king has the highest authority, and has the right of life and death over all resources and all people in the entire kingdom.
(1) Operate any file, directory or process
But this operation is within the highest permission range of the system. Some operations cannot be completed even by root with super privileges. For example, the /proc directory, /proc is used to reflect the real-time status information of system operation, so even root cannot write to it.
(2) For system management involving the global system
Hardware management , file system management, user management and related system global configuration, etc... If you are prompted that you have no permissions when executing a certain command or tool, most of them require super permissions to complete, such as using adduser to add users. This can only be done by a user with super privileges.
Recommended learning: Linux video tutorial
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