OAuth

OAuth is an open authorization standard that lets an application access part of your data on another service without needing to know your password. Instead of handing over your credentials, you authorize a specific, limited permission, and the service gives the application a token ✕ A token is the smallest unit of text a language model works with: usually a word or a piece of a word. Pricing and limits are measured in tokens. More in the glossary → that acts as a temporary, revocable key. This is what happens when you click "Connect with Google" and an app asks, say, to see your calendar but not your emails. Its advantages are that you never share your password, that permissions are granular and that you can revoke them whenever you like. It is worth distinguishing that OAuth handles authorization — what an app is allowed to do — while authentication — who you are — is solved by layers like OpenID Connect. It underpins much of today’s logins and integrations between services.