About classes

Hey Im new here, Used to play ePT (Im TheDeath, hey 2kill, yaperri-dono )and now im going to give PW a try. I'm sry if this sounds too noobie or a bad question, but id like to know more about classes, so i can start it right tomorrow ( im still downloading the client =X). I have searched in the wikis and guides, but i still dont get it very well, so i thought some experienced guy/girl could tell me more. I can say i like aggressive classes (archer, mage) because u need to plan ur attack, being caught by surprise is bad ( in other words u need to make the first strike). So id like to hear more about the offensive classes (archer, mage, priest, possibly summoner) so i can make my choice. Thank you!