BackTrack Linux is now Kali Linux (Since 2013)

Auditor Security Collection and Whax merge to create BackTrack

Live CD and live USB capability

BackTrack 2

Kernel 2.6.20

Metasploit2 and Metsploit3 support

Redesigned menu structure

BackTrack 3

Kernel 2.6.21.5

Saint and Maltego added

BackTrack 4

Kernel 2.6.34

Massively improved hardware support

Official FluxBox support

BackTrack 5

Based on Ubuntu Lucid LTS

Kernel 2.6.38

BackTrack Linux becomes Kali Linux

Support for BackTrack Linux ends

Complete platform rebuild

Based on Debian

Streamlined package updates synced with Debian