adding sharepoint website user

I want to add a user to sharepoint website.

I loggin the website as website owner and add a user in the people and group inside the website-members(created by default) and give him full permissions.Still he is not able to access the website.

Now i add the user by accessing he sharepoint administration website-application management\policy for web pplication.

Can somebody please let me know as why this happended and if that is the riht thing then what is the use of people and group feature insode website owner's webpage

[550 byte] By [CanUHelpMe] at [2007-12-30]