Matching Pairs GadgetsOnline version gadgets, modern technology by Marga Czyk 1 It is an optical disc to store digital data 2 You can switch on the tv, or change the channel with it 3 This device makes a loud sound at a specific time 4 You can make and receive telephone calls everywhere with it 5 You can listen to music everywhere using your MP3 Player compact disc mobile phone remote control alarm clock