Which device is NOT considered an input device?

A monitor is not considered an input device because its primary function is to display output from the computer, rather than inputting data into it. Input devices are used to send data or commands to the computer, allowing users to provide information or control the system. Examples of input devices include keyboards, which allow text input, mice, which enable navigation and interaction with on-screen elements, and scanners, which digitize physical documents for the computer to process. The monitor, however, serves as an output device, presenting visual information generated by the computer's processing, making it essential for user interaction but not for data entry.