U2F/FIDO is superior to other 2sv (2-step verification) authentication systems because it's a "what you know and *what you have*" system that makes such a difference. The phisher doesn't have your key. When Google implemented this internally, successful phishing dropped to zero. Using U2F/FIDO security keys to protect your Google account: https://support.google.com/accounts/answer/6103523 https://help.twitter.com/en/managing-your-account/two-factor-authentication
