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OAuth is used for authorization purposes. UMA can be used to give access to someone without giving their credentials. OAuth allows you to link your amazon wallet with your swiggy without giving them the amazon credentials. The following is the flow that UMA follows: The resource owner set’s some permission on who can access the resources from the resource server and also controls the permissions on the Authorization server. The requesting party is the application to whom the user grants permission to access resources on behalf of the user. The requesting party will be someone (not you) wants to link amazon pay wallet with their Swiggy account.