I couldn't find the appropriate section for this post, but this seems like a good place.
This man will teach you almost everything computer related. You can prepare for you comptia exams for those looking to get into the IT field or those looking to gain further understanding. He teaches hardware, networking, cryptology, and
pentesting (nmap) the nmap course you pay for but I have you covered.
This link should show up as a online PDF Wich is downloadable via any browser I believe ( Chrome and Firefox are my favorites ). And you can download the PDF
directly to your iBook library, Free is love lol hope you guys enjoy peace! .