OAuth
OAuth is an open standard for delegated authorization that lets users grant an application limited access to their accounts (e.g. 'Sign in with Google') without sharing passwords.
OAuth 2.0 lets a user authorize an app to act on their behalf via an identity provider. The app receives a token rather than the user's credentials, limiting exposure.
It powers familiar 'Sign in with Google/GitHub' flows and is the backbone of social login. Combined with OpenID Connect, it also conveys identity, not just authorization.
Backends typically integrate OAuth through an auth service or identity provider, then issue their own session or JWT for subsequent API calls.
Related terms
OAuth in Kolaybase
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