The DPS indicated on the character screen for a character is just over 30,000. The DPS indicated by the floating white "damage" numbers seem to be lower than this number. I've read some answers here, but have not been able to explain this difference. The character screen DPS includes CC and CD, averaged out?
The DPS (damage per second) or damage amount shown on your character sheet screen is typically much higher than the damage per hit (shown above monsters in white/yellow text). There are several reasons why:
Your attack speed is faster than 1 attack per second - excluding other factors, if you attack 2 times a second, then the damage per hit can be half of your dps
Many attacks have an area of damage around the primary attack point (for instance, the Monk's Fist of Thunder or Crippling Wave attack). Since these attacks have an area component, usually they multiply your damage by a factor and then apply the damage to each enemy hit. For instance, excluding other factors, if you do 30k DPS and you attack a group of enemies with an attack that does area damage, it may do 15k to the primary target and 10K (or less) to area targets.
There is a random component to damage (typically noted by a damage range on weapons (100-300 for instance)) ; if you do exactly 10k damage to an enemy for one hit, you may do less or more on the next hit with the same weapon on that enemy
Enemies are different levels, enemies in inferno go up to level 63; while your character can only achieve level 60. Since the DPS is the damage you do to EQUAL level monsters, you will do less damage to monsters that are above you
Elemental attributes: some enemies have a certain elemental affix and will be naturally resistant to attacks of that type - ie. a fire weapon will do less damage to a fire construct.
Critical hits: The DPS on your character sheet takes into account your Critical Hit Damage and Chance. This means that if you have some critical hit chance, but you get an 'unlucky' streak of no crits, your damage is lower. BUT, over time, the crits will come and average it out.
All of these combined may make your damage per hit much less than your DPS, and some of them (if not all) affect skills as well.
DPS stands for "Damage Per Second", which is an estimated amount of damage you will do per second, assuming you are attacking one enemy that is the same level as you.
This is not the same as damage per hit, which is the damage that floats above monsters. If you had a weapon that did one attack per second, you attacked one mob and you averaged out your hits (including crits), then this would be your damage per second. However faster weapons, and crits (or non crits) will cause different amounts of damage to monsters.
So damage per second is an average of the amount of damage, including crits, that you will do per second per mob. Since you generally attack faster than once per second, the amount of damage per hit will be lower.