Your users need to sign up, authenticate, retrieve their password, change their password, etc. Building your own system takes time and resources, so why not do what developers do best…abstract it away! Places like Twitter, Facebook, and Google have given developers the sweet gift of third-party authentication, allowing your users to use their existing credentials to access your application. Learn about the pros and cons of offloading authentication to these services and see how they work while exploring options using both OpenID and OAuth.
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