Context: Assistive listening devices in many theaters and similar spaces use arrays of infrared LEDs to send sound to listeners' receivers. Light-emitting diodes (as well as semiconductor lasers) are used to send data over many types of fiber optic cable, from digital audio over TOSLINK cables to the very high bandwidth fiber links that form the Internet backbone. For some time, computers were commonly equipped with IrDA interfaces, which allowed them to send and receive data to nearby machines via infrared.

Question: Where are infrared LEDs used in everday life?
Answer: theaters

Question: How are LEDs used in theaters?
Answer: to send sound to listeners' receivers

Question: LEDs can send data over what type of cable?
Answer: fiber optic

Question: What type of fiber forms the backbone of the internet?
Answer: very high bandwidth

Question: Where are infrared non-LEDs used in everyday life?
Answer: Unanswerable

Question: How are non-LEDs used in theaters?
Answer: Unanswerable

Question:  LEDs can't send data over what type of cable?
Answer: Unanswerable

Question:  What type of fiber doesn't form the backbone of the internet?
Answer: Unanswerable