A first Sight about Linux 😎- Permission

            Linux permissions are a crucial aspect of the operating system's security model, allowing users to control who can access and modify files and directories. There are three levels of permissions in Linux: user, group, and others.

            User permissions dictate what actions the owner of the file can perform on it. By default, the user who creates a file or directory is the owner. There are three types of permissions that a user can have on a file: read, write, and execute.

            Read permission allows the user to view the contents of a file or list the contents of a directory. Write permission allows the user to modify the contents of a file or create, delete, and rename files within a directory. Execute permission allows the user to run a file or access the contents of a directory.

        Group permissions specify what actions members of a specific group can perform on a file or directory. This is particularly useful for shared files or directories where multiple users need access. Just like user permissions, group permissions can be set to read, write, and execute.

        Others permissions determine what actions all other users on the system can perform on a file or directory. By default, others have read and execute permissions but not write permissions. This means that any user on the system can view the contents of a file or directory and run an executable file, but they cannot modify the contents.

                To set permissions on a file or directory, you use the "chmod" command followed by a string of characters that represent the permissions for the owner, group, and others. Each permission is represented by a digit from 0 to 7, with 0 meaning no permission, 1 meaning execute only, 2 meaning write only, 3 meaning write and execute, 4 meaning read only, 5 meaning read and execute, 6 meaning read and write, and 7 meaning read, write, and execute.

For example, to give the owner read, write, and execute permissions, the group read and execute permissions, and others only execute permissions on a file, you would use the following command:

chmod 751 file.txt

This command would set the permissions on "file.txt" as follows:

• The owner has read, write, and execute permissions (7)
• The group has read and execute permissions (5)
• Others have only execute permissions (1)

       It's important to understand Linux permissions and utilize them effectively to maintain the security and integrity of your files and directories. Using strong permissions can help prevent unauthorized access and modification to sensitive data.