Player identification number

A Player identification number (often referred to as PID) is a unique identification number that each player possesses. It previously determined the priority between two or more players when simultaneously performing tasks throughout RuneScape. The update on 17 September 2013 removed the system, with each action now being completely randomised.

Calculating
A random player I.D. is assigned to a player upon logging into the game and it changes each time they log in. Prior to the player I.D. system, priority between players was based on the players' IP addresses.

You could approximate your player I.D. by following a player and having them run. The delay between your friend moving and your character moving was believed to be caused by your player I.D. If the delay was longer than normal, you have a higher player I.D. than the other player.

Examples of Player I.D. Prioritization
The following list contains examples of when a player I.D. became a factor in determining which player has the higher and lower priority.
 * Dueling - Determined which player gets the first hit in a duel or when both players simultaneously attack each other at the beginning of the duel.
 * Setting up barricades in various activities - Determined if another player can walk through a barricade that was just set up by another player.
 * Closing doors - Determined if a player can walk through a doorway while another player closes it at the same time.
 * "Catching" in RuneScape Classic - Player I.D.s determines if a player can "catch" another player when PKing in the Wilderness. "Catching" is a RuneScape Classic term where after three rounds of combat, a player runs from their opponent and the other player can "catch" them by chasing after them and attacking them again, bringing them back into combat.
 * Picking up items amongst other players - Affected which player gets an item if two or more players pick it up at the same time.
 * Competing for items like chronicle fragments, in which two players could click at the same time and be within similar distance to the item, but only one player can get it.