Backtrack Linux will be different than any linux flavor you have used before. Why? you ask.  Well simply because it has more industry expertise, specific application, and intended purpose than any other linux flavor.  Backtrack was made by the security engineer for the security engineer, through addition and refinement backtrack has become an irreplaceable security auditing tool.

If you are interested a great book to order and read as you go along is
The Basics of Hacking and Penetration Testing: Ethical Hacking and Penetration Testing Made Easy

About the Book:
The Basics of Hacking and Penetration Testing serves as an introduction to the steps required to complete a penetration test or perform an ethical hack. You learn how to properly utilize and interpret the results of modern day hacking tools; which are required to complete a penetration test. Tool coverage will include, Backtrack Linux, Google, Whois, Nmap, Nessus, Metasploit, Netcat, Netbus, and more. A simple and clean explanation of how to utilize these tools will allow you#xA0; to gain a solid understanding of each of the four phases and prepare them to take on more in-depth texts and topics. This book includes the use of a single example (pen test target) all the way through the book which allows you to clearly see how the tools and phases relate. Each chapter contains hands-on examples teach you how to interpret the results and utilize those results in later phases Written by an author who has practical experience as a Penetration Tester and who has taught “Introduction to Penetration Testing” for 5 years Utilizes Backtrack Linux distribution and the “core” tools required to complete a penetration test