How can permissions be granted to users in Linux?

In Linux systems, users can add permissions using the chmod command. Here are some commonly used commands:

1. To add read permissions to a file: chmod +r filename
2. Add writing permission to the file: chmod +w filename
3. Add execute permission to a file by using the command: chmod +x filename
4. Grant full permissions to the file: chmod +rwx filename

You can use the chown command to grant specific users or user groups permissions. For example, to give user1 read permission: chmod u+r filename

Additionally, you can also use numbers to represent permissions, for example, chmod 755 filename means giving all users read, write, and execute permissions, giving the file owner read, write, and execute permissions, and giving users in the file’s group read and execute permissions.