|Perks are permanent buffs applied individually to every player. The player is required to select a perk on the startup screen, the selected perk being applied to the player upon spawning. Each player is required to select one perk, and their decision cannot be altered after spawning. A suggested perk is Ninja, as you are less likely to have zombie detection problems from afar and it is easier to stalk an enemy, prey, or perhaps escape them yourself. Another could be Vitality if you are considering to be a Bandit, because you may find yourself in low-health situations often and thus may have higher odds of surviving.
As of update 6/23/14, it is possible to chose two perks at an expense of credits (purchasable by Robux). However, choosing perks that contradict each other cancels out the ability. For instance, Ninja and Vitality; Ninja decreases noise whilst Vitality increases it, this cancels out both abilities thus you generate the same noise as a player without Ninja/Vitality perk.