Well for starters it’s an automatic document feeder? But what exactly is it? A lot of times when I’m writing about a printer for a review or for a deal, I mention that it’s good that the printer has an ADF. An ADF is a tray that you load up with papers and put into your printer for scanning or copying. This allows you to scan/copy multiple pages without having to do them one at a time. Obviously this will save you a lot of time because you aren’t having to lift up the lid on your printer in order to keep doing each individual page. This feature used to be somewhat rare on standard multifunction machines and then for a while they used to hold a small amount of sheets. These days high-capacity ADFs are becoming more common.