The Shotgun is an over-under break-action weapon that appears in Alan Wake. Like the flashlight, there are different variations of the shotgun; In this case, only two: the Double Barreled Shotgun and the Pump-Action Shotgun.
The double-barreled shotgun, known more informally as simply "The Shotgun", holds only two rounds. It does three times more damage per shot than the revolver, and both barrels can be fired in quick succession, but it needs to be constantly reloaded. It's possible to hit several enemies with a single shot from using both the shotgun and pump-action shotgun (doing so awards the Two For the Price of One achievement). It modelled after Browning O/U 12 Gauge.
The Double Barrel Shotgun packs a harder punch than the Revolver and has a semi-decent range. However, this power is offset by the fact that it can only carry two shells when fully loaded and its slow reload time. The Pump-action on the other hand, has lower power, slightly less range, but more rounds (Eight). The only weapon that beats it in power (besides the flare gun or flashbangs) is the Hunting Rifle.
The Shotgun is the only gun in Alan Wake that was not brought back in Alan Wake's American Nightmare.