Stalkers are stage two infected that hide, circle you and strike from cover. They keep a runner's sight and speed but fight harder, and in Part I they are rare: two main encounters for Joel and one in Left Behind for Ellie.
Stealth rarely works, because a moving stalker is almost impossible to grab and they run for cover when they see you coming. Let them come to you and answer with the shotgun or flamethrower. One shotgun blast or a rifle headshot drops one. Stalkers can override Joel's punches, so stun them with a thrown brick or bottle, or use a melee weapon.
Ellie only has her pistol and switchblade against them. Throw bricks straight at a stalker to stun it, then stab it before it recovers.
Hunters
Hunters are the armed civilians who took Pittsburgh from FEDRA and now ambush anyone passing through to strip them of supplies. You fight them through the Pittsburgh and The Suburbs chapters.
Image: Naughty Dog / PlayStationBloater
Bloaters are stage four infected covered in armor-like fungus. They are slow and blind but kill you instantly if they grab you, and they throw bursting sacks of mycotoxin from range. Fire is the way to beat them.
Clicker
Clickers are blind stage three infected that find you by the clicking sound they make. Their grab kills instantly unless you carry a shiv and have the Shiv Master upgrade, so most players deal with them quietly or with fire.
FEDRA
FEDRA, the Federal Disaster Response Agency, is the military government that runs the Boston quarantine zone. Its soldiers are the best-equipped enemies in the first chapters, and you fight them while smuggling Ellie out of Boston.