A person who uses his or her expertise to gain access to other people's computers to get information illegally or do damage is a ________.
A person who used his or her expertise to gain access to other people's computers to get information illegally or do damage is a Hacker.
A hacker is an individual who uses computer, networking or other skills to overcome a technical problem. The term hacker may refer to anyone with technical skills, but it often refers to a person who uses his or her abilities to gain unauthorized access to systems or networks in order to commit crimes. A hacker may, for example, steal information to hurt people via identity theft, damage or bring down systems and, often, hold those systems hostage to collect ransom.