Which of the following is NOT an Input Device? 

The correct answer is Speaker.

Key Points

• A speaker is an output device, not an input device.
• It is used to produce audio output that can be heard by the listener.
• Speakers convert electrical signals into sound waves.
• Commonly used in computers, televisions, and other audio systems to play music, sounds, and other audio files.

Additional Information

• Input Devices:
  • Devices that send data to a computer for processing.
  • Examples include keyboards, mice, scanners, and bar code readers.
• Output Devices:
  • Devices that receive data from a computer and present it to the user.
  • Examples include monitors, printers, and speakers.
• Keyboards:
  • Primary input device used to enter text and numerical data.
  • Consists of various keys including letters, numbers, and function keys.
• Mouse:
  • A pointing device used to interact with a computer's graphical user interface.
  • Allows users to click, drag, and select items on the screen.