dedicated servers, what does that even mean?

im always hearing how some games have dedicated servers and some dont. what does that mean. give me an example of a game with dedicated servers and a game that doesnt. what advantages is there. just wondering since im always reading this.

Unreal Tournament 3 - Dedicated servers

Gears of War 2 - No dedicated servers

Dedicated: A lot less lag, if any.

A dedicated server does nothing but host a game, as opposed to a "player" sever (proper term?) where someone in the game is hosting it and playing in it.

Honestly it means pretty much what it says. It's dedicated to the game in question. You can use a server for many things at once.. you could host a website or many websites, host an email application, host a database tied to an ecommerce storefront and host a 1 or 10 games all on one server. That means that systems memory, bandwidth and processing power has to be used to accomadate all those things at once which means that everything on that server would be running less than optimal. When it's dedicated it means they have a server that's sole purpose is what it's dedicated to ie... the things listed above like processing power don't have to worry about anything else but serving up that game.

Now don't get me wrong the reason I mention websites isn't because that's what MS is doing with there servers, i'm just giving you an example of what's not dedicated.

edit> I should have mentioned this is adding to what the above poster said for another kind of non dedicated server

A lot of dedicated servers are paid for by players.. It's not un-common for a clan or a group of people or even an individual to pay out of pocket to put up a server that is open to other gamers. Just pointing this out because yes, sometimes companies will absorb this cost but just as often or even more often it's coming out of gamers pocket to play on said servers.

Yes, but there's still the possibility that someone closer to the server has a better connection.