Question

How can I get information about the loged in user when I load a random website page ?

I need to grab a profile field to customize the page look

thanks

Answer 1

The current user information is always available as a global, so you just do:

global $user;
// $user will now be a stdClass object representing the current user, logged in or not
// If you are only interested in logged in users, a standard check would be
if (0 != $user->uid) {
  // Do something for/with logged in users
}

The anonymous user will have uid 0, the admin (first) user will have 1.