ok, i am fairly new to WoW, and i am wondering what the difference between the realms is, like pvp, role playing, etc...

There is no difference between Normal and Role Playing realms. There is also no difference between PvP and PvPRP realms. The players in the Role Playing realms tend to role-play more, but the content is the same. The single difference between Normal/RP and PvP/PvPRP realms is how characters are PvP-enabled, or "flagged" in game vernacular. In Normal/RP realms, PvP mode is nearly always optional except in battlegrounds and enemy cities; you can enable and disable PvP mode at will. This is not the case in PvP/PvPRP realms, where PvP mode is still optional in friendly zones that cater to level 20 and below (Alliance and Horde zones), but mandatory in all other zones (contested and enemy zones). Your PvP mode in contested and enemy zones automatically turns on three seconds after you enter the zone, even if your PvP mode is set to "Disabled". If your PvP mode is turned off when you enter a friendly zone, you are still flagged for 5 minutes afterwards as in the Normal realms. - LJS

all realms contain the same content. just people go to realms for different things, so its likely that if you enjoy a certain activity, people in a real of that activity will be there.

For example, if you like PVP, join a PVP realm. Others who like PVP will also be in that realm. Same for role-Playing and other stuff too.