A Phreaker is a person who knows way too fucking much about phones and how they work and how to get illegal free calls and much more just by using a phone and they use boxes like the blue box that generates a blue 2600
hz sound that is a basic 'hack' of a phone.
someone: 'Dude...I ran out of minutes and cant call anywhere..
me: 'Ha need help, eh? I'm a phreaker...I can help you..'