Ranger

Ranger is a Fallout, Fallout 2 and Fallout Tactics perk.

Fallout
With each level of this perk, your chance of a hostile random encounter is lowered.

Fallout 2 and Fallout Tactics
With this perk, you gain +15% Outdoorsman, you are more likely to avoid and choose your random encounters, and have more chance to find special encounters.

Bug

 * In unpatched Fallout 2, you gain +20% Outdoorsman instead of +15%.