An automatic document feeder (ADF) is a device that allows multiple pages to be fed into a printer or scanner automatically. This feature saves time by eliminating the need to place each page manually. ADFs are commonly found in multifunction printers and copiers, making them useful for businesses and home offices. ADFs can handle various paper sizes and types, enabling users to scan, copy, or fax documents quickly. They often include features like duplexing, which allows for double-sided scanning or printing. Overall, ADFs enhance productivity by streamlining document handling tasks.