remember that ALMOST EVERY ROCK/POP CHORUS EVER MADE HAVE THESE CHORDS..... I IV V VI obviously you can play I V IV VI ecc. ecc. or this other progression I IV V

where I IV V VI means the grades(i don't know if is it correct in english) of the scale...for example the C scales has the C D E F G A B notes and you can build up from these notes these chords C Dm Em F G Am Bhalf dim. so this progression: I V IV VI means that you play C G Am F

if you were in the key of D the progression would be D A Bm G and so on...

take a look at the BED OF ROSES chorus....it goes VI V IV I
IN THESE ARMS I VI V IV
BORN TO BE MY BABY VI IV V I
STICK TO YOUR GUNS I V IV VI
and the same for almost every BJ/AEROSMITH/ADAMS/POISON (and thousand of others) songs
and so on....always the same 4 chords just in different order (but usually the same) and different keys