Apple :: Launching An Application At Login

What is the method to automatically launch an application when the user logs in. Does it involve putting an alias of the app in some specific "startup" folder, like in Windows?

I am trying to install an older scanner driver on my new MBP, which I was only partially able to do. The "button manager" app, would not install automatically using the installer app. Hence, in order for the buttons on the scanner to work, I have to first manually launch the Button Manager. On my older MB, it would launch at login, so it was resident at all times. I none such difficulty installing the same driver package on the old MB.

I find it odd that my new MB has so many quirks that my 1 year old MB unibody does not. They are running exactly the same OS version. Hmm And Migration Assitant left a boatload of stuff (such as this), unmoved.