Kali is the successor to BackTrack, and is a Debian-based Linux distribution that includes hundreds of penetration-testing tools pre-installed and ready to go. Just boot it from a USB drive or live DVD and you’ll have a penetration-testing—or “hacking”—environment with all the tools you might want just waiting for you to fire them up.
More frequent updates
The biggest change is the shift to a rolling release model. Now, you can simply install Kali Linux 2.0 on a computer and the latest versions of security tools will be provided to you as normal updates. There’s no need to wait for Kali Linux 2.1 to get the newest stuff. An eventual Kali Linux 2.1 would simply be a snapshot of the current software available, which 2.0 users would already have upgraded to.
The developers also tout a new upstream version-checking system, which will notify them when the various security tools included in Kali are upgraded. This means Kali’s tools will be upgraded more frequently.
A new desktop environment
Kali Linux 2.0 includes a variety of software upgrades. It’s now based on Debian 8 “Jessie”, and that brings the Linux 4.0 kernel along with improved hardware support and, importantly, better wireless driver coverage.
The main system image has moved to GNOME 3, which is the developer’s favorite desktop environment. But Kali also officially supports KDE, Xfce, MATE, Lxde, e17, and i3wm. The GNOME system means the main Kali system will now take up a bit more RAM—768MB minimum for a full GNOME 3 session. If this is too much for you, there’s now a “Light” version of Kali Linux you can download instead. This includes the lighter Xfce desktop environment and a smaller collection of useful security tools.
Kali Linux also provides upgraded ARM images so you can run it on the Raspberry Pi and various Chromebooks. Nethunter images for Android devices have been upgraded, and there are also official VirtualBox and VMware images you can download.
Kali Linux 2.0 wasn’t the only security-focused Linux distribution to release a new version timed with DefCon, either. Tails 1.5 just debuted with a variety of fixes, upgrading the anonymity-focused operating system favored by Edward Snowden.