What should I understand when someone says "You must be expert with OS"?
As the title said what should I understand from this sentense. I will be more specific, I want to become a malware analyst. And I know that I must become expert with most of the OS out there. But I'm confused what does "expert" means, should I be able to program my own OS or I must be familar with concepts like memory managers, schedulers etc.. This is so confusing for me. I thought to buy a book but I don't now which one, also should I buy one or learn for microsoft academy and tldp. I will be very grateful to anyone how help me to clear the confusions.