Processing Account Login

Hi Everyone When I login to PayPal a total of 3 web pages are used: 1 – A screen for the user to type in their user name & password 2 – A screen saying “ Logging in “* 3 – My Welcome / Personalized Account Summary Screen * During the 2nd web page my PHP script is going to be accessing the mySQL database to check the login credentials. - I would like to know how this is done - I would like to know how to re-direct the user to a “incorrect password” screen if this is the case - I would like to know how to re-direct to a “security question” screen as a secondary step for those users who want this additional security (such as what I am offered through my online banking sign in process) I don’t know what an effective search query is on Google. I don’t mind (nor will I take offense) on being directed to a tutorial. I want to ensure what I am putting into production is high quality and not hap hazard. Thank you for any help you are able to provide me with. Ron Piggott www.TheVerseOfTheDay.info