OAuth? ,OpenID? Neither? Which one should my site support?

Question

I working on a new website and wanted some advice/feedback on OAuth vs OpenID vs Standard site owned username/password.

Answer 1

You can combine all of them and get the best out of it, but it depends on your design choices.

For example if you are using Java, you can configure Acegi(Spring Security) to allow openID along with your normal authentication mechanism.

openID has OAuth extensions

OAuth has openID extensions

It's up to you...