This book covers Windows rootkits, although most of the concepts apply to other operating systems as well, such as LINUX. We focus on kernel rootkits because these are the most difficult to detect. Many public rootkits for Windows are userland rootkit because these are the easiest to implement, since they do not involve the added complexity of understanding how the undocumented kernel works.-This book covers Windows rootkits, although most of the concepts apply to other operating systems as well, such as LINUX. We focus on kernel rootkits because these are the most difficult to detect. Many public rootkits for Windows are userland rootkit because these are the easiest to implement, since they do not involve the added complexity of understanding how the undocumented kernel works.