Loud long lasting noise every time i flush?

loud noise which can be heard by both my neighbours when i flush the toilet, gets worse as i put the tap on aswell.
I have looked through other peoples questions and found that some answers are saying i will need a new diaphgramn or valve? is this correct? If so these terms mean nothing to me so could anyone explain what im looking for/to replace? PLEASE HELP?? (I HAVE JUST A STANDARD OLD TOILET)