The title and description says it all, I'm going to start 2 forums and I want to know what's the tasks of a moderator in a forum and what he do on it.

Besides just being a regular member?
Contribute to the content of the forum by posting, apply the rules of the forum, maintain some control and issue discipline, promote membership in the forum, assist the Admins, help members, edit errant posts, issue warnings (and guidance) to members, have fun, meet new people, learn stuff and pass the information along.

A moderator is someone who should be a role model for every other member to follow. One to dedicate time to forum to moderate posts so that they are not breaking the rules the forum has set, advertise the forum, making it more popular and also trying to encourage posting in a forum. In a way, he has to lead the forum he is moderating forward. Ideas to improve the forum and make it more attractive for guests are also plus points. His posts has to be of a certain quality, there is certainly no room for 1-liners or posts which will not contribute to the forum. A Moderator is scouted out when he starts doing things what a normal member should and much more, but its the quality of posts which catches one's eye.

For me the first and most important task of a moderator is to behave correctly and politely, to make the forums a good place to stay, where users fell comfortable. And of course when you act as another user (posting) you should be a model of behaviour, because you have some authority and if you do something wrong, then it seems to the rest of the users as if that conduct is allowed. The indispensable quality of a moderator must be a well developed common sense which must be applied always.

The more "physical" tasks are erasing, moving, editing posts if necessary (you should not abuse on your powers) and always according with the rules of the forums if there are ones. You have to be careful and try not to be favorable to anyone because others would complain about it. You have both to warn and help users to move along the forums.

Yo say that you're going to moderate two forums. I don´t know how many people will be there (so I don´t know how much work) but you should have time to do your tasks properly, even more if you're the only moderator.

I don´t think that advertising the forum and that things are really moderator tasks. Of course if you like the forums you are probably going to tell people to enter, but for me it's not an obligation of the mod. If you´re not the admin probably you can be the link between users complains, questions, etc and the administrators. Anyway it depends on the kind of implication that the admins want from his mod. If you're also the admin, then you should do everything, because no one is going to do it for you, of course.

Well I thought I put my 1 penny worth of thought about this and we all know about my track record here

But through my wonderful experiece as a mod and admin on other sites I would say that this would the following order

1. Learn and know everything about how a forum works, because each one is different in it's own little ways and the more you know the easier maintaining a forum gets
2. Support (wait for the eye rolls and what not) If everyone doesn't support in help maintaining a forum in every aspect, then it could flop I seen that happen quite a lot when I was helping forum design for people back in the day.
3. Respect (waiting for the eye rolls again) you have to earn it and if your a crappy mod people will know and most likely complain about it they usually do.
4. Rules (no comment there)
5. Need good Content, Like I have told hundreds of people content is everything it has to be unqiue and useful don't try to post up old stuff won't help because you can find it else where I would know I am guru in finding stuff on the net. If you don't have good content then your site will slowly die
6. Advertising and affiliation are a big aspect of getting your forum well known, it doesn't get you a million hits thats content and search engines job to do that. It doesn't matter who you advertise with its a simple link and everyone ones google loves links.
7. Mods also need to be resourceful as well if your mod has no clue whats going with in a forum how will they be able to answer peoples questions, this more or less falls in line with # 1 and #2
8. Experience mods need to train up hte new mods so they know where everything is had ( I done that here and on asta as well)
9. It's a Position like a anything else, regaurdless if you good at what you do, if people don't respect you then your position is meaningless and the only thing you got is authority, big whoop so you can something others can't. Of course that is coming from my experiences in the military
10. Patience, if you don't have it and can't stand people asking the same question 30 billion times then your not fit to be a mod.

Their is more I think but those are like the top unwritten rules to having a good mod.

Contribute, discipline, organize, manage, support, and advertise are the basic requirements for a moderator. They should get new people to come to the forum[s] [provided the person would be interested...no use having people there that don't want to.], do their own to contribute by posting, manage and organize forums by removing bad things, adding new things, rearranging things for clarity, etc., and most importantly HELP out with any forum members that might need it.

An administrator is basically the same thing, but as far as forums are concerned, they do a lot more of the backend management by controlling and changing what goes on with the forum system itself, and less with the content of the forums.

Hope that makes sense.

Wow .... thanks a lot for these explanations.. I didn't expect this ever , ok I got what I need now thanks again