kawiyowee, degrees are in a wheel , crank, cam gear flywheel and round objects have 360 degrees in them as i'm sure you know .well when the motor turns the pickup,crank trigger is adjusted to a certain place, tooth on gear on the wheel ,certain spot on the flywheel or whatever and were that(pick up,crank trigger and so on) points is a certain degree on the wheel(fly wheel,tooth on gear,whatever) thats were degreeing your cam comes in and timing your motorand degrees as you know now are btdc as well atdc there all around the wheel can't use em all but thier there. hope this helps.