"Ancient pattern automatic pistol. Weak and short range, but quick."
The pistol is a light, single-shot firearm in RimWorld with low damage per shot; short time between shots; moderate range; and moderate accuracy.
Due to its short ranged, high fire rate nature; the pistol is a good choice for shooters with low post-processed accuracy (95% or less), but other weapons such as machine pistols and pump shotguns are still better options if available. Its effective range is around 14-18 tiles, but it's sufficiently accurate to be utilised up to its maximum range - if the shooter is also capable of doing so, but it'd be better to equip the shooter with an LMG or charge rifle if they could do so, as they have similar range.
Its main advantage lies in its cheapness, but you can still get better 'bang for the silver' if you invest slightly more in an 'automatic' weapon - and the same rule applies to crafting costs.
Its fast fire rate combined with its lower DPS makes it an optimal weapon for practicing shooting skill.
Pistols can be purchased from outlander and orbital weapon traders for a relatively low price, or obtained from outlander and pirate raiders. Pistols can also be crafted at a machining table once the machining research is completed; from 30 steel, 2 components, and 15,000 (250 secs) of work.
Conclusion & Comparison
As to be expected, the pistol is the lowest ranking firearm in the game overall with its mediocre range and accuracy, and sub-par damage - but a pistol still outclasses the short bow by a significant margin. The pistol is also outclassed by even the machine pistol, and therefore significantly below the heavy SMG and pump shotgun; all of which shadow the pistol in terms of damage output either by being automatic weapons, or just superior stopping power - of which the heavy SMG almost combines both of these attributes. The great bow also outguns the pistol, and arguably the pila does too.
Overall, the pistol remains a somewhat useful weapon in the early game, but you'll gradually see your stock of better weapons increase as you dispatch of more hostile raids.