This code is run every time the computer detects a key press.  A variable "keyCode" holds the numerical value that represents the specific key that was pressed.  For example, if I press the UP arrow, keyCode will be a 38.


void keyPressed(){
 print(keyCode + " "); //This gives you the key code number for any key you press during your program 


  if(keyCode == 38){ //38 is the key code for UP
     speedy = -2; 
  }else if(keyCode == 40){ //This is for down
     speedy = 2; 
  }

  //Keep adding else if's to get all the keys you need for your program

}