A "demon" in software refers to a background process that runs continuously to perform specific tasks without direct user interaction. These tasks can include managing system resources, handling network requests, or monitoring system performance. Demons are essential for maintaining the smooth operation of various applications and services. Typically, demons are initiated during system startup and operate in the background, allowing users to focus on their primary tasks. They can be found in various operating systems, including Unix, Linux, and Windows, where they help automate processes and improve overall system efficiency.