Pixel Tracking is a method used in digital marketing to monitor user behavior on websites. It involves placing a small, invisible image, known as a pixel, on a webpage or in an email. When a user visits the page or opens the email, the pixel sends data back to the server, allowing marketers to gather information about user interactions. This technique helps businesses understand how effective their advertising campaigns are by tracking actions like clicks, conversions, and page views. By analyzing this data, companies can optimize their strategies to improve engagement and increase sales.