What input device is used to convert a printed document into an electronic document?

The scanner is the input device designed specifically for converting hard copy documents, such as printed pages, into digital formats. It operates by capturing the image of the document and translating it into a digital file that can be stored, edited, or shared electronically. This process typically involves the use of light sensors to create a digital representation of the original document.

In contrast, a keyboard is primarily used for data entry and does not have the capability to convert printed materials into electronic formats. A printer, on the other hand, is the device that produces physical copies of digital documents rather than converting printed items back into digital form. Finally, a monitor is an output device that displays digital content but does not handle the conversion of printed documents into electronic versions. Thus, the scanner is essential for bridging the gap between physical and digital documents.