Wow, very informative, thanks!!

Well besides using SQL server studio management how else can u set a user id and password?

So the initial catalog is basically saying if "database1" is attached to the sql instance already, then just read from that? What happens if the database name doesn't exist for the initial catalog value u set, does it then attach itself to the instance?

So how do i adjust privlidges on the mdf file or the SQL server itself so that you can locally connect to a DB without using the user instance property?

Also one last question, typcially how are things setup when people use SQL server as their backend for their applications?

Do they just leave the .mdf file on the users machine, and specify the Server path as some other remote path?

Also, how when you specify the SQL Server instance name, how is that obtained normally? I mean yeah it's common that an SQL Express install is named as SQLExpress, but what about other versions, and what if someone renamed it, what happens in terms of deploying an application, can you dynamically determine if an SQL Server install is present and detect the named instance?

Sorry for all these questions, but i can't find a good guide on a thorough introduction to it.

Thanks again for everyone's help.