PHP Possiblilities Question

Before I start researching how to do it, I want you all to tell me that it's possible.  I hate deciding in my head that something is possible with PHP, b/c I think it should be, then not be able to figure out how to do it.

Anyway, my question....

I want to be able to put a log in for clients on my new company site, That they can log in on a main page & it will forward them to the page with their information, that no one else can get to.  I haven't started development yet, but my brain tells me that I could set up a admin user login like I have on my personal site, but add a section in the database that will tell the PHP where to forward the user after they log in.  Is my reasoning reasonable? ;D

I need this because instead of having to email clients files & billing, they would just have a log in where they could download it off the server.  I have this right now, but I just send them their URL (my clients have sub-domains on my domains) then I have a simple password protect on the page.  I have seen people with a client page, where the clients click on their name then enter their password, but I think that looks unprofessional & with my clients Client A does not need to know I am working with Client B.

Thanks for your input in advance!

Of course this is possible and I believe it is easy too.

Olaf has a class for user management, you may use it or you can create something more simple to fit your exact needs.