Input device - online puzzles

In computing, an input device is a piece of computer hardware equipment used to provide data and control signals to an information processing system such as a computer or information appliance. Examples of input devices include keyboards, mouse, scanners, digital cameras and joysticks. Audio input devices may be used for purposes including speech recognition.

Input devices can be categorized based on:

modality of input (e.g. mechanical motion, audio, visual, etc.)

whether the input is discrete (e.g. pressing of key) or continuous (e.g. a mouse 's position, though digitized into a discrete quantity, is fast enough to be considered continuous)

the number of degrees of freedom involved (e.g.