A web beacon is a small, transparent graphic image, often just a single pixel, embedded in a webpage or email. It is used to track user behavior, such as whether an email was opened or a webpage was visited. Web beacons help website owners and marketers gather data about user interactions and improve their services. These tracking tools work by sending information back to the server when the image is loaded. This allows companies to analyze user engagement and tailor their content or advertisements accordingly. Web beacons are commonly used in conjunction with cookies and other tracking technologies to enhance online marketing efforts.