A data broker is a company or individual that collects, analyzes, and sells large amounts of personal information, such as consumer purchasing habits, online behavior, and demographic data, to other businesses. These brokers act as intermediaries between data sources, such as social media platforms and online retailers, and companies looking to target specific audiences for marketing or research purposes. While data brokers can provide valuable insights for businesses, their practices have raised concerns about privacy and the ethical use of personal data.