The Yubikey 5 supports the FIDO2 protocol, which in turn supports not only today’s two-factor authentication but also strong, single-factor, hardware-based authentication. And now with support for FIDO2 in addition to U2F, the YubiKey offers the broadest options for strong authentication, including not only two-factor authentication, but also support for single-factor passwordless backed by public-key cryptography. The YubiKey offers superior security by combining hardware-based authentication and public key cryptography to effectively defend against phishing attacks and eliminate account takeovers. The National Institute of Standards and Technology no longer recommends using SMS as a second authentication factor. Even multi-factor authentication solutions like one-time passwords (OTP), temporary passwords sent via text message (SMS), and/or mobile push (notifications that look like text messages and alerts) are vulnerable to phishing attacks. The number one method for stealing credentials is through phishing attacks. Authenticating with username and password alone is no longer sufficient. Stolen passwords account for 81% of security breaches. YubiKey 5 Series: Key Benefits Strong Authentication that Protects Against Phishing and Eliminates Account Takeovers For a full list of those services, see Works with YubiKey. Note that for individual consumers, the YubiKey only works with services that support one of the many protocols provided by the YubiKey. As the principal inventor of the U2F and FIDO2 authentication standards, Yubico is a recognized, award-winning leader in IT security. It is easy to use, radically reduces IT costs, defends against phishing attacks, and eliminates account takeovers. The YubiKey strengthens security by replacing passwords with strong hardware-based authentication, including multiple protocols and public key cryptography. The YubiKey 5 Series security keys offer strong authentication with support for multiple protocols, including FIDO2, which is the new standard that enables the replacement of password-based authentication. In addition to describing the new features in the YubiKey 5 Series, this quick start guide points to the documentation on how to get started using YubiKeys in the 5 Series.