/'hAt/ (noun)
from Old English hete; akin to Old High German haz hate
1: a : intense hostility and aversion usually deriving from fear, anger, or sense of injury b : extreme dislike or antipathy : loathing
2: an object of hatred
3: (FFXI) a measure of how much a monster wishes to attack a character
When a monster is attacking one member of a party that member is said to have "the hate." As I'm sure most of you know, this can change based upon spells cast and special abilities used. The three biggest contributors to getting hate appear to be dealing damage to the monster, casting spells, and using the warrior ability provoke.
Managing Hate
The big divider between a pile of attacking n00bs and a party is the organization of hate management. In a good party only one or two characters are recieving all of the monster's attacks (tanking). For those party members their contribution to the party's success isn't measured in damage dealing but in their prevention of having anyone else do any damage taking.
This burden isn't 100% upon them, however. Healers and damage dealers must regulate their activities a little to avoid distracting the monster from the tank(s).
Now at high levels, say 75ish, I believe a great tank (paladins are what I have the most experience with) can keep the hate off of melees nearly 99% of the time (blms can probably always get hate with two ancient magics in a row). Playing ranger, I have seen a wide variety of tankers, and some of them cannot keep hate off me when I only use ranged attacks and no abilities, and others can keep the hate off me no matter what I do (the only real exception ebing if I start a fight with Slug Shot, Barrage, Slug Shot).
One of the more vivid examples happened when fighting Seiryu with two different teams. With one team, I got hate just by ranged attacking. With the other team, 5 of us rangers with bard support went all-out (leading off with Slug Shots 20 seconds after the fight started) for the entire fight and Seiryu never turned on us. I do not know what the paladins in either case were doing, though I know for sure in the second case they didn't even have theif trick support. Point is, there are things you can/must do in order to keep the hate.
Anyone good at tanking want to add something, please?!