However, this permission has no effect on directories unless the execute permission is also enabled. For directories, the write permission allows a user to modify its contents (create, delete and rename files in it). Write: For a file, the write permission allows a user to modify and delete a file.For directories, the read permission allows the user to view the names of files and other directories stored in it.

Read: For a file, the read permission allows a user to view the contents of a file.

In Linux, we use permissions to control what a user can do with a file or directory. These are system users and groups, which are used to run background processes securely. When running these commands, you will notice that there are a number of other users and groups that you didn’t create. The first part of each line contains the group name. Similarly, you can view the groups on your system by viewing the /etc/group file, by running: cat /etc/groupĪgain, each line contains the details of a user. Specifically, you can see the username at the beginning of each line, before the first. Here, every line contains details of a user.

If you want to view the users on your system, you can view the /etc/passwd file by running the following command: cat /etc/passwd A particular user is associated with a “default group”, and can also be a member of other groups on the system. In order to make managing users easier, you can add users into a “group”. Every user has some properties associated with them, such as a user ID and a home directory. Linux uses the concept of users to separate various people who use the computer. Users and groupsīefore we discuss the concept of “ownership”, let us first look at “users” and “groups”. In this article, we will learn these concepts, and how you can change them using various commands. You can use these concepts to control who can access and modify files.

Linux is a multi-user operating system, and it ensures the security of files with the concepts of “ownership” and “permissions”.

Linux default chmod