A touch screen functions as both an input and output device. According to the CompTIA ITF+ FC0-U71 Official Study Guide:
"A touchscreen display is a hybrid device combining input and output. It shows visual output like a standard monitor but also allows the user to interact directly by touching the screen."
"Input devices allow users to provide data or control signals (e.g., keyboard, mouse, touchscreen)."
"Output devices show results from the computer's processing (e.g., monitor, printer, touchscreen)." Touchscreens display information (output) and receive user input through touch (input). They do not perform storage, networking, processing, or logging.
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