How to interpret waveformData

I am using Soundcloud Waveform JS to create my own audio visual effects and was wondering ... what does waveformData array

of floating points look like

waveform.update({
  data: [0.5, 1.0, 0.5, 1.0] // what does the data really represent?
});

      

        
        
        
      

    

interpreted relatively?

• to him peakData
  
  ?
• song timeDuration
  
  ?
• what does each mean array value
  
  ?