A non-player character, called NPC for short is a character not controlled by players in RuneScape. Mmors.com where sell cheap RuneScape Gold will give you a simple introduction of it.

Players in RuneScape can speak to NPCs, the latter can only talk to a player at a time. Remember that the NPCs are not attackable, only monsters are attackable. NPCs consist of bankers, store owners, quest contacts and civilians. They can sell items, deliver quests, restrict access to some places and perform important duties.

Most NPCs have no useful function, but they can provide atmosphere and interesting conversation. NPCs names have a yellow color. Note that NPC will reset to its respawn location if a player blocks the path for an NPC for a long time. In addition, most NPCs have one life point and are weak to crush, and they are able to run for a short time with lag.