All the main issues of assembly programming are explained in detail and intelligibly. Reviewed Intel processor instructions, 16- and 32-bit registers, coprocessor basics, real-time memory segmentation, keyboard and serial port management, disk handling, and more. Describes how to develop a harmless non-resident virus and antivirus against this virus, how to write a file shell (such as Norton Commander or FAR Manager), and how to write resident programs. Each chapter consists of an explanation of a new topic, a description of program algorithms, numerous examples and answers to frequently asked questions. Corrections have been made to the second edition and new examples have been added.