Linux was developed in 1991 by Linus Torvalds and it is one of the derivative of UNIX. Linux is also the least popular operating system for workstation installation.

Linux is open source operating system which means that anyone can download it, use it and can modify it according to their will. Linux is basically a command-line operating system. However, many distributions (distros) come with a desktop environment (DE) that provides a GUI for Linux users. One of the most popular distros for casual users is Ubuntu. There are also other distros in Linux like Linux Mint, Debian, KDE, and Red Hat.

In the Ubuntu interface, the topmost Launcher button is the Dash button, which is almost equivalent to Windows’ Start button. We install applications in Ubuntu mostly through CLI. The following figure shows the Ubuntu interface: