URL of the current user’s website is stored in this global variable. It is set using the cookie in the pluggable functions set_current_user($id, $name='') and get_currentuserinfo() defined in [wordpress root folder]/wp-includes/pluggable-functions.php.
Plugin and theme authors can use this global variable if they need to reference the current user’s website URL.
Back to full list of global variables.
Technorati tags: user_url
