Need Clarification on a couple of terms: Mitigation and Negate

Caroloces

Being a newcomer to MMOs, I've encountered these 2 terms frequently, and I always have the nagging sense that I don't fully understand their meanings in an MMO context. Mitigation means to lessen the damage you take from an enemy NPC or player, but what particular game mechanic is employed when this term is used? Is it healing? Damage shields? Or is it the type of armor that you wear?
Negate is even more fuzzy to me in its meaning. I sense that it means to counteract a spell or an attack in some fashion, but not entirely sure how this works.

Some concrete examples from the different classes or different situations would sure be a great help.

jhharvest

Mitigation is everything that reduces the incoming damage. Higher armour rating gives you mitigation, championpoints give you mitigation, blocking gives you mitigation. Some passives and active skills also increase your mitigation. They all reduce the damage being done to you. Damage shields I wouldn't count in mitigation - they are just a buffer on which your mitigation doesn't even affect (essentially your damage shields have 0 armour rating).

Negate is a sorcerer class ultimate that stuns NPCs and silences enemy players.

Vangy

Mitigation.

Most commonly this refers to any kind of damage reduction you have. The most common thing that every character has access to regardless of race/build in terms of mitigation would be resistances. This show up on your character sheet when you hit C. Look under physical and spell resistance. Resistances are calculated via this forumula;

Mitigation = (resistance - 100) / (level*10). So if you have 20 k resistance @v16 ; (20k-100) / (66*10) = 30.1% mitigation
Bear in mind this is before applying the numerous debuffs and penetration people have. The most common ones being major breach and concentration via light armour. So typically youd have about ; (approximately since I cant rmb exact numbers);

20k - 5000 (from penetration) - 5000 ( from breach) - 5000 (sharpened weapons) = 5k

So final mitigation before other buffs = 7.5% lol

There are other examples of mitigation like flat out damage reduction via racial buffs or spells. There are some buffs like volatile armour from the DK skill line that give you around 5k to both phy and spell res etc etc.

Negate -- (Negate magic)

The sorcerer ultimate that plants a nice big purplish translucent bubble on the ground. When your in it you are silenced.

FriedEggSandwich

Good answers. It's worth mentioning that things like dodge-roll, cloak, reflect, damage shields and even heals can also be considered damage mitigation as they all reduce incoming damage, but usually people are referring to armour when they talk about mitigation.

Caroloces

Thanks for your helpful answers. On mitigation, you've all affirmed what I thought was true. On Negate (which I thought was a general term, like mitigate), I was surprised to find it to be a specific ability (ultimate). I guess I have to cultivate a sorcerer character to learn more about that class!