FIDO is an acronym that comes from the Latin fido, meaning ‘to trust’, which was popularised by Abraham Lincoln—who borrowed it to name his dog. It’s a fitting name for man’s best friend, and just as appropriate in the security world, where trust is key. A more technical reference, FIDO (Fast IDentity Online), emerged in 2012 and is backed by a range of big tech and finance players like PayPal, Lenovo, Google, Visa, and Microsoft, known collectively as the FIDO Alliance. Based on public key cryptography, FIDO is a set of protocols designed to support authentication of just about any type. This includes fingerprint, biometrics, One-Time Passwords (OTP), Trusted Platform Modules (TPM), USB security tokens, near-field communication (NFC), and Bluetooth for mobile devices—with API support to handle the heavy lifting for developers. Since arriving on the scene, the FIDO Alliance has published three specifications: Universal 2nd Factor (U2F), Universal.