Compare U2F and UAF security standards
u2f (universal second factor) is a 2-layer security authentication standard that uses external hardware (usb, bracelets ...) so the level of security will be higher than sendingHow to secure your accounts with U2F security key?
u2f is a new validation standard. u2f security key is small usb device. to login, you will not need to enter the authentication code provided from an application or sms anymore,