What's the difference? I'm guessing one does better against armored foes and the other does better against unarmored foes.

DAM = damage = the damage done per bullet/shot/hit/etc.
DPS = damage per second = averaging out the damage based on fire rate

One is raw damage per instance of doing damage, and gives some indication of the ability to pound through DT. The other gives you the general damage output to compare to other weapons.

Unless I'm mistaken, DPS doesn't take reload time into account.

Queue

DAM generally means that it can punch through armor easier, while DPS is better for hordes of lightly armored foes.

Basically, think a Rocket Launcher Vs. a Assault Rifle. The Rocket Launcher has high DAM but low DPS, while the Assault Rifle has low DAM but high DPS. I don't need to tell you what is better suited for what.

Ok. Thanks.

High dps weapons do poorly against armored foes unless your using AP rounds, lower dps weapons have a higher base damage to start with and so can usually punch through an enemies armor with regular or surplus rounds. as said above high dps is good on lightly armored foes while high dmg weapons work bet on armored targets.

The two aren't mutually exclusive though, you could have something that's both high DAM and high DPS. You can also have something that's low on both. Each simply indicates a specific property of the weapon: damage per hit, and damage averaged over time. If something's high enough damage per hit, it's probably going to be pretty respectable damage per second as well.

Queue

Well, for one, Riot Shotgun has high DAM AND high DPS. Which is why I love it so much.

Secondly, there's a bleed-through effect: the damage you deal cannot be lower than 20% of your weapon's DAM EVEN IF the weapon's DAM is completely negated by enemy DPS. This means that you CAN bring down armored foes with a low DAM, high DPS weapon, even without AP ammo, you just need to score a lot more hits.

As a hypothetical example, suppose you have a rifle with DAM 30 that fires one bullet per second, and an SMG with DAM 10, and you're firing at a Giant Radscorpion with DT 18. The SMG's damage is completely negated by DT, but because of the bleed-through effect, it still deals 2 damage points on each shot. Which means that to match the rifle's damage output, the SMG needs to fire 15 bullets per second.

I once needed to bring down two Giant Radscorpions (DT 18) which respawned out from under me on a save/load. I found it easier to do it with a 9mm SMG (DAM 14, DPS 154 without mods) than with Lucky (DAM 30, DPS 82.5)

Also worth noting that a weapons DAM is generally the additional damage amount you get from a crit. Having said that, higher damage weapons are better for sneaking than high DPS weapons, since you can potentially do enough damage to kill the enemy with the first shot: you'd never pull this off with a low DAM weapon high DPS.