So before jumping on to command lines, I'm going to give you an introduction to Linux. So, Linux is a family of free and open source software operating systems. They are built around the Linux kernel. Linux kernel is an operating system kernel, which was first released on September 17 1991, by Linus Torvalds. Linux distribution is an operating system which is made from software collection and is based on Linux kernel and package management system. So there are different Linux distributions available, like a boon to Kali Linux, Debian, and so on.

And in this course, we are going to use Kali Linux and no matter what Linux distro You have the commands are going to be same throughout all the Linux distributions Linux command line. So in Linux we write the command line in Terminal. The external environment has a terminal emulator for writing all the commands. different environments have their own different terminal like the GNOME desktop environment has no terminal and Katie has console