Later in the book, I define hacking as being:
The art of manipulating a process in such a way that it performs an action that is useful to you.
Which I think is a true representation of a hacker in any sense of the word, whether a computer programmer who used to hack code on mainframes back in the day, so that it would perform an action useful to him, or a modern computer attacker with a very different goal and set of ethics. Please bear in mind that when I use the term hacker in this book, I am talking about a network-based assailant trying to compromise the security of a system, and I don't mean to step on the toes of hackers in the traditional sense, who have sound ethics and morals.