What makes the interactive whiteboards able to interact with?

Question: What makes the interactive whiteboards able to interact with?
- Keywords:
- Royal Society of Chemistry: Find out more about:
  
  interactive
  
  whiteboard
Asked by ladypotatoes to Martin on 16 Mar 2015.
- Martin Wieczysty answered on 16 Mar 2015:
  
  The board has lots of pressure pads that when you push on them they will send a signal to the computer telling the computer where you touched the board. It is similar to how touchscreen phones are interactive, except they pick up small changes in electric current rather than pressure.

Question: What makes the interactive whiteboards able to interact with?