管理员权限是如何工作的呢？
As well as the files that you create, your computer has a number of files which are needed by the system for it to work properly. If these important system files are changed incorrectly they can cause various things to break, so they are protected from changes by default. Certain applications also modify important parts of the system, and so are also protected.
The way that they are protected is by only allowing users with administrative privileges to change the files or use the applications. In day-to-day use, you will not need to change any system files or use these applications, so by default you do not have administrative privileges.
Sometimes you need to use these applications, so you may be able to temporarily get administrative privileges to allow you to make the changes. If an application needs administrative privileges, it will ask for your password. For example, if you want to install some new software, the software installer (package manager) will ask for your administrator password so it can add the new application to the system. Once it has finished, your administrative privileges will be taken away again.
Administrative privileges are associated with your user account. Administrator users are allowed to have these privileges while Standard users are not. Without administrative privileges you will not be able to install software. Some user accounts (for example, the “root” account) have permanent administrative privileges. You should not use administrative privileges all of the time, because you might accidentally change something you did not intend to (like delete a needed system file, for example).
总之，管理员权限使您可在需要时更改系统的重要部分，又可防止您意外操作。
What does “superuser” mean?
A user with administrative privileges is sometimes called a superuser. This is simply because that user has more privileges than normal users. You might see people discussing things like su and sudo; these are programs for temporarily giving you “superuser” (administrative) privileges.
管理员权限有何用处？
更改重要系统设置需要用户拥有管理员权限，这可以防止您的系统被有意或无意地损坏。
如果您总是具备管理员权限，就有可能无意中更改重要的系统文件，或者运行一个损坏系统的程序。只在需要的时候才临时取得管理员权限，可以减少发生这些错误的风险。
Only certain trusted users should be allowed to have administrative privileges. This prevents other users from messing with the computer and doing things like uninstalling applications that you need, installing applications that you don’t want, or changing important files. This is useful from a security standpoint.