A black hat hacker is a term used to describe a person who engages in unethical or malicious hacking activities. These individuals may use their skills to gain unauthorized access to systems or to steal sensitive information. They may also use their expertise to engage in cybercrime or to disrupt the normal functioning of computer systems. Black hat hackers often operate outside the law and may use their knowledge and expertise to engage in activities that are illegal or harmful to others. In contrast, white hat hackers are ethical hackers who use their skills and knowledge to help organizations improve their cybersecurity posture and to identify and fix vulnerabilities.