Access control: In the field of computer security, access control is to provide different access permissions for different users, that is, different users have different operational capabilities for different resources.


Windows:
There are three common file system formats under Windows, FAT, FAT32, and NTFS.
On the Windows platform, turn on the "computer" and we can see the drive disk. Each drive has its own root directory structure, which creates multiple trees standing side by side.
In Windows, there are two types of users: computer administrators and restricted users. Windows is often set as an administrator. As a result, everyone can install and modify the system software at will. As a result, the virus software is hard to prevent and the security of Windows is relatively poor.


Linux:
There is an important concept in Linux: everything is a file. The default file system used by most Linux distributions today is ext4.
In Linux, there are four types of users: root, regular users, same group of users, and other users. The Root user has the highest privileges and can perform any operation on the computer system. However, root users generally log in only during system maintenance, such as adding a new user or installing an application. Generally is the identity of ordinary users to log in, ordinary users can not modify the file under the system file, so the possibility of the virus software to modify the system program is greatly reduced, so as to increase the security and reliability of the system.