Duo two-step login protects your personal information and the university's data by ensuring you are you when you login to your OSU account. It works because it relies on something that only you know (your password) and something that you have (a mobile device, hardware token, etc).
There are several available options for authenticating with Duo two-step login - you can use your mobile device, a hardware token or security key, or even Touch ID on compatible MacBook laptops.
The Duo Mobile app is the fastest and easiest way to use Duo, available for iOS and Android devices. This authentication method works by sending a "push" to your device to verify your login attempt.
If you have a MacBook laptop with a fingerprint reader and use Google Chrome as your web browser, you can use your laptop for Duo authentication. See if your device is compatible and add it as a Duo device.
If you prefer having a dedicated device for Duo, you can use a hardware token or purchase a security key.