Additional Drupal Modules: OpenID
The idea behind OpenID is to allow a user who has already registered on a major website, like Google, to log in to your Drupal site using his Google account information instead of creating a new account on your site. OpenID supports a number of major website logins. A user can also create a master login at Openid.net that will allow him to log in at any site that allows OpenID.
If you turn on the OpenID module, you open your site to users you haven't personally verified. This doesn't matter if your site is mainly informational or if you want a large user base. But if you allow your users lots of privileges — such as posting unmoderated content to message boards — you may not want to use this module.
To activate the OpenID module, follow these steps:
Click Modules on the Dashboard menu bar.
Select the OpenID check box.
Click Save Configuration.
The next time a visitor arrives at your home page, she will see the normal login form and a link to use an OpenID login. If she clicks that link, the login form changes to prompt for her OpenID.