Hello Patil1, Vinod (Contractor-NBCUniversal)
Thanks for reaching out. Microsoft Graph is a RESTful web API that enables you to access Microsoft Cloud service resources. Please refer to article for information on the using of Microsoft Graph web API. If you are referring to Microsoft Graph SDK, the SDK is a set of libraries designed to simplify building high-quality, efficient, and resilient applications that access Microsoft Graph. Microsoft Graph does supports various languages such as C#, Python, PowerShell, etc. Please refer to article on Microsoft Graph SDK overview. If this does not answer your question, please clarify what you mean by 'exact reasons for converting to Graph APIs from REST?'.
Thanks.