Hi,
are you talking about those three dots?
... dot dot dot, ellipsis, etc.If so, they are used in informal writing, for example in forums, chat rooms, blogs, etc., by some people (like me, LOL), and they are used to get many effects, for example when you don't know what to say, when you want to make a pause, when you are thinking, when you are leaving out something or you are not sure there's nothing more to add... and so on.
In formal writing they are never used that way though.

A little example. In novels you might find something like this:
"Maybe... we should call him! Or maybe..." But Mary jumped up, and without letting him finish the sentence shouted "No! Don't!"Sorry, I'm not a good writer. Not even a bad one. I'm not a writer, period!