embeding postgre

Hi,

I have a question, because i cannot find any information in online docs
(maybe i'm just blind :P).
I'm want to build application with embedded database, but i also need a
possibility to have one global database, which can be accessed from internet
(ability to synchronize between remote and local/embedded database). I heard
from somone that i could use PostgreSQL, but I cannot find any information
that confirms or denies it. And one more thing, i'm interested only in free
solution ;).
Sorry for if i made some mistakes, english is not my native language.

I'll be appreciate for any information.