What Is BackTrack? So now that you are familiar with Linux, let me introduce you to BackTrack. BackTrack is a Linux penetration testing distro developed by Offensive Security especially for ethical hackers and penetration testers. It contains all the popular tools and software used for pen testing a variety of services, networks, and devices. BackTrack 5 is the latest version of the Linux penetration testing distro at the time of writing this chapter. It comes in two flavors: Gnome and KDE. Gnome is an Ubuntu-based Linux operating system that has officially been introduced only in the latest version of BackTrack. Here is a screenshot of BackTrack 5.