It is a extremely popular way for Office 365 developers to work with SharePoint sites, lists/libraries, and list items/documents.
JSON Light is an open standard that allows developers to provide in the header of the request how much metadata is returned.
SharePoint APIs in conjunction with the Office 365 API Preview by using the Azure Active Directory auth bearer token.
The common consent framework authentication approach in standalone web and mobile device applications to take advantage of all the existing SharePoint API.
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