Add caption Hello guys welcome back to HackerHeaven,today we will learn about the system security of the linux distros...very preciesly..so..we are going to look at this essential part of system security and introduce the following commands: ● id – Display user identity ● chmod – Change a file's mode ● umask – Set the default file permissions ● su – Run a shell as another user ● sudo – Execute a command as another user ● chown – Change a file's owner ● chgrp – Change a file's group ownership ● passwd – Change a user's password i hope you enjoyed my previous articles too... here are some things straight forward but instead you have too know it.. command : id output : ubuntu@ubuntu:~$ id uid=1000(ubuntu) gid=1000(ubuntu) groups=1000(ubuntu),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),108(lpadmin),124(sambashare) ubuntu@ubuntu:~$ So where does this information come from? Like so many things in Linux, from a couple of text files....