The YubiKey is a hardware authentication device manufactured by Yubico to protect access to computers, networks, and online services that supports one-time passwords, public-key cryptography, and authentication, and the Universal 2nd Factor (U2F) and FIDO2 protocols[1] developed by the FIDO Alliance. It allows users to securely log into their accounts by emitting one-time passwords or using a FIDO-based public/private key pair generated by the device.