Running Applications at Startup/Login Time
In Windows you put a link to an application in the startup folder at C:\Documents and Settings\username\Start Menu\Programs\Startup. On the Mac you open System Preferences and go to the Accounts subsection. There you click on the Login Items tab to see the applications that will start when you login.
Select an application from the list and click on the minus sign (- in the lower left) to remove it. Click on the plus sign (+ in the lower left) to bring up a finder window showing the Applications folder and select an application to add it to the list of startup or login items. If you click on the checkbox in the Hide column then no icon for the application will be placed in the menu bar.