Beginner with pgadmin, sorry

Hi,

I am a beginner with pgadmin (version 1.14.3 on windows).

I would like to make a local DB on my computer.

But I do not manage to connect to serveur, I have tried:
Name : My DB
Host: MyComputer
Port TCP : 5432

Please, could you tell me where I have made an error?

I have checked the documentation, but exemples are on unix and I work on 
windows.

Thanks beforehand,