FIDO aims to replace passwords with open authentication standards. It defines specifications for authenticators like security keys and fingerprints to verify users during the login process. The FIDO Alliance has over 250 member companies working to develop specifications like UAF, U2F, and the upcoming FIDO 2.0, and ensure interoperability between implementations. FIDO authentications use public key cryptography to authenticate users locally on their devices and then with online services, without exposing any secrets that could be used by third parties or across multiple accounts.