Abilities is a tab in the menu. Abilities are separated into three categories:
Skills are use-recharge abilities that can be swapped in the menu at anytime and does not require points in order to unlock and use them.
Talents are active abilities that, when unlocked, are activated when very specific conditions are met. E.g. a player will receive a bonus for performing a headshot on an enemy.
Perks are passive abilities that remain active at all times once unlocked. Perks can stack with each other allowing bonuses to be increased.