A black market is an illegal network or marketplace where goods and services are bought and sold outside of official, regulated channels. These markets often deal in items that are illegal, stolen, or restricted, such as drugs, weapons, counterfeit products, or stolen data. Transactions on black markets bypass government oversight and laws, making them risky for both buyers and sellers. In cybersecurity, black markets are notorious for trading stolen personal information, hacking tools, and malware, contributing to various forms of cybercrime.