Black hat hackers are individuals who use their technical skills to exploit computer systems and networks for malicious purposes. They often seek to steal sensitive information, disrupt services, or cause damage to systems. Their activities are illegal and can lead to significant financial losses for individuals and organizations. Unlike white hat hackers, who help improve security by identifying vulnerabilities, black hat hackers operate outside the law. They may work alone or as part of organized groups, and their actions can have serious consequences, including legal penalties and harm to victims' privacy and security.