The Ultimate Linux Shell Scripting Guide

Donald A. Tevault - but you can call him Donnie - got involved with Linux way back in 2006, and has been working with it ever since. He holds the Linux Professional Institute Level 3-Security certification, and the GIAC Incident Handler certification. Donnie is a professional Linux trainer, and thanks to the magic of the internet, teaches Linux classes literally the world over from the comfort of his living room. He's also a Linux security researcher for an IoT security company.