Deskewing is the ability of the scanner driver to detect that the item being scanned is not straight. When the deskew option is turned on the driver will attempt to straighten the image so that the resulting scan is level from left to right. This feature is useful when attempting to OCR a document; however, it is important that when scanning from the flatbed the page be aligned to the alignment arrows. When scanning from an ADF the input paper guides should be flush to the side of the pages being scanned.

When a document has printing or pictures on both sides of the page this means that it is a duplex or two-sided document. A duplex scanner will scan both sides of a document at the same time.