Rtfm: Red Team Field Manual
Level: All levels
The Red Team Field Manual is a must-have when it comes to Hacking Books. This is not a book you use to study, this is a Red Team Reference Guide. This guide contains the basic syntax of commonly used Linux and Windows commands. It also includes Python Scripts and Windows PowerShell tips.
I personally always take this book with me when I am on assignment or on any hacking related trip. I have a lot of personal notes and additions to it as well. For the price, I definitely recommend picking up a copy. Put it under your pillow while you sleep, carry it with you at all times. Great little book.