Perfect Pitch (or Absolute Pitch) is a skill that involves being able to identify musical notes without hearing a reference tone.
Using the Perfect Pitch Trainer
Click "Start" to listen to the first note and bring up the note selection display. Click on the note that you hear. If the colour changes to red, then you got the note wrong. Green = Good. Click the panel again to hear the next note. Your accuracy percentage will appear below so you can track your progress while using the tool.