OAuth 2.0 is an authorization framework that allows applications to obtain limited access to user accounts on an HTTP service, such as Facebook, GitHub, DigitalOcean, and others. It works by delegating user authentication to the service that hosts the user account and authorizing third-party applications to access the user account. OAuth 2.0 defines four roles: resource owner, client, resource server and authorization server. With regards to API design, OAuth 2.0 can be used to protect API endpoints by ensuring that the client applications having valid access tokens can only interact with the API. It provides detailed workflow processes and a set of protocols for the client application to get authorization to access resources.
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