Instead, it refers to a theory of authentication where you prove that you should have access with: Something you know, something you are, or something you have. In practice, two-factor authentication (2FA) is using two things to log in to a site or service, but that's not where the name comes from. This hydra of a hardware key works exactly as it should and comes packed with features the competition can't match, but is hampered by limited support on iOS and a comparatively high price. This tiny double-ended device sports a USB-C connector on one end and an Apple-compliant Lightning connector on the other.

The final frontier for Yubico has been the iPhone, which it finally addresses with the YubiKey 5Ci. Yubico's YubiKey line has been a go-to choice for simple, hardware two-factor authentication for years. How to Set Up Two-Factor Authentication.How to Record the Screen on Your Windows PC or Mac.How to Convert YouTube Videos to MP3 Files.How to Save Money on Your Cell Phone Bill.

How to Free Up Space on Your iPhone or iPad.

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