Fast Identity Online (FIDO) refers to a set of open authentication standards the enable a service provider to leverage existing technologies for passwordless authentication.
FIDO standards such as FIDO2, Universal Authentication Framework (UAF), and Universal Second Factor (U2F) are developed by the FIDO Alliance, an industry consortium of technology leaders such as Apple, Google, HYPR, and Microsoft. These innovators have allied themselves to reduce the tech landscape's over-reliance on passwords. Solution providers build value atop FIDO standards so that enterprises can quickly and easily deploy FIDO architecture that leverages smartphones for access to services in the way that Common Access Cards (CACs) do in far more secure work environments. FIDO finally makes public key cryptography (PKC) commercially viable whereas before, PKC and biometrics (also a FIDO element) were unrealistic to implement outside of mission-critical settings.
The term "FIDO" may refer to the architecture, overall vision, or alliance itself and is gaining momentum with multimillion-user deployments across customer segments, notably in financial services whose enterprises are early FIDO adopters. When a solution advertised as FIDO, it is important to distinguish between FIDO Certified solutions that have undergone rigorous security, interoperability, and scalability testing and "FIDO compliant" or "FIDO supported" claims which are little more than marketing language.
"The bank I work for is deploying FIDO authentication across its internal user population of 1,200 workers. Once deployed we'll be able to access company resources at work and remotely across all devices using our personal smartphone. We'll also abandon the need for security tokens since the solution is de-facto MFA."