Random encounter

From The Vault

A random encounter is a universal RPG situation, it most often occurs when the Player is transversing a distance across the world map or a dungeon, resulting in a conflict with a randomly chosen opponent. In Fallout however, random encounters are only encountered on the world map and can be as simple as a trader wishing to show you his wares, to finding a tin man who needs to be oiled...

Not every encounter is hostile. Not every dangerous encounter involves aggressively minded NPCs (such as Stampede or Dehydration encounters in Fallout). Not every encounter even has an NPC on its map (Old battle encounter). Some random encounters are unique, and happen only once during the course of the game (or not at all) - these are commonly known as Special encounters.

The kind of encounter you get depends on many factors. The main one is player's location on the World Map. Others may be his Outdoorsman Skill, his Karma or Reputation, as well as his previous actions during the game.

See also: Fallout 3 random encounters