so im finally getting going with the webapps in Arc.
however if i really want to run a server and have information stored, lets say i create a simple forum.
do i need to use mysql then? or is there some sort of database system included in Arc?
You could use Arc templates, which are an easy way of saving and loading Arc objects to/from text files. That's what this forum uses. I believe kens' site has some documentation for this, or you could look at the news.y source code.
If you want to use a SQL database instead, someone wrote an interface for it and posted it to the forum (maybe also on Anarki?) but I can't find it with Google.