PvP stands for player vs player, and often refers to combat between a number of players.
A PvP world allows you to fight other players throughout RuneScape, with the exception of a few safe areas. These include banks, respawn points and some guilds. An icon will appear to let you know when you're in a safe area.
When you enter a PvP world a skull icon appears above your head - something we call being 'skulled'. Dying while skulled means you lose all your items, and you won't get to keep your three most valuable items like you normally would. if you retaliate against someone who has attacked you, this does not leave you skulled.
As with all other RuneScape worlds, you lose any unprotected items you are carrying when you die.
When you defeat another player in combat on a PvP World, you have a chance to get rewards in the form of items. These items can come straight from your opponent inventory or be selected randomly from a series of objects - some of which are unique to PvP worlds.
You will notice that you receive better items by spending more time in PvP worlds - especially in hot zones and by taking more valuable items into combat. A picture of a fiery skull will appear on your screen if you are in a hot zone.
There are exciting new items that may be dropped, available only on a PvP World. These items will degrade over time when worn or while in combat, and cannot be fixed. When they finish degrading they will turn to dust.