There are currently two types of turrets in the game, those being Ranged and Melee turrets. All turrets require power to function.
Main Article: Laser Turret
A stationary turret that fires lasers at anything within its range, even through walls.
Main Article: Rocket Turret
Just like the laser turret, except it fires rockets.
Main Article: Slammer Turret
This is a stationary spinning metal pole that slams into anything that steps into its radius, be it player, vehicle, or Leech.
Main Article: L-Slammer Turret
A larger version of the slammer turret.
Vertical Slammer Turret
Main Article: Vertical Slammer Turret
Does not currently do anything other than spin in a relatively useless way.