The net is getting a little safer for Google users Thursday, as the company is unveiling an option for Google users to lock down their accounts with more than just a password.

Starting Thursday all Google users can choose to turn on a so-called “two-factor authentication” feature, which will require them to type in a special, short-lived second password in addition to their normal password to get into their account. Users will be able to get the codes via SMS or a phone call, or use smart phone apps for Android, iPhone and Blackberry to generate the codes.

The idea isn’t new, even though this i...