Headless or Standalone server

Hi guys,

I have no doubt about there is a lot of person who ask those questions, but I’m in trouble to find some clear answers for my questions. So, first, sorry to probably ask again to informations which has been already answered.

So, here’s my precises questions, and fell free to link another post as answers if you think it’s pertinent :

First, I read a lot of stuff about headless servers but those articles or posts are old but if I have understand correctly :
Yes, there is a headless server system, but it’s only for the pro version?

Or is it possible to make it with the free version in Unity 4? (A lot of articles I’ve read are dated from 2009-2010 and some of them talk about a release of Unity with headless servers).

And what are we talking about when we said “headless server”?
I want to make a FPS and I want to distribute a server side program (without any graphical parts, just a console) free for people who doesn’t buy the game. It’s possible with?

Or if I have to program a server side program, what I’ll need? Can I program it just with the base C# libs, or C , or Java (haha why not, I just askin).

I’m not a beginner programmer, so I’m not affraid to do this, but I dont want to start a from scratch server if I can do it easily in another way.

I hear about RakNet, but I do not really understand what is it? I think it’s the library which Unity use for Network base.

So, there is a lot of question, I hope it can be easily answered for you guys.
Thanks for your future answers.

A headless unity instance is just unity running without any graphics, in a console window. This requires Unity Pro. If you want to make a multiplayer and distribute a server .exe (like half-life, counter-strike, etc.) you need this.

RakNet is a networking library.