Ok if you have the occassional zit or two once or twice a month don't panic, but if you get pimples, especially the big ones that hurt under your skin you better see a dermatologist. Those ones are the ones that are more prone to scarring.
I have zits once in a while, but luckily mine don't scar, I've heard the ones that hurt scar more easily.
Sabrina
Review of Best Acne Treatments