Difference between Office 365 REST Api and Microsoft Graph - api

Question

I would like to know difference between Office 365 REST API and Microsoft Graph, since we could find similar functionality for both of these.
https://msdn.microsoft.com/en-us/office/office365/howto/rest-api-overview
Following is the text from above link:
Office 365 API functionality is also available through Microsoft
Graph, a unified API that includes APIs from other Microsoft services
such as Outlook, OneDrive, OneNote, Planner, and Office Graph,
accessible through a single endpoint and with a single access token.
If there is no such difference, do you plan to deprecate any of these?
Thanks

Answer 1

Microsoft API is one endpoint solution to access the Office 365 services like mails, calendars and .etc. By using the graph api, no more obtaining separate tokens for different services or calling a different endpoint for each API.
Some features may be available on the individual service endpoints,
but not yet on Microsoft Graph. We are working hard to bridge these
gaps. If you require one of these features, you can use the individual
endpoint in the meantime. Check the release notes for details on the
Microsoft Graph features in preview and generally available.
For details, you could refer the document Choosing your API endpoint.

Answer 2

The Documentation state that Office 365 API functionality is also available through the Microsoft Graph, a unified API that includes APIs from other Microsoft services such as Outlook, OneDrive, OneNote, Planner, and Office Graph, accessible through a single endpoint and with a single access token. We recommend using the Microsoft Graph in your apps when possible.
Also see this answer it says
Our recommendation is for you to use Microsoft Graph as long as it has the features/APIs you need in production to support your production apps, or at least in Preview to support app development. This makes it easy for you, in the future, to expand your app functionality requiring access to multiple Microsoft services, without changing endpoints. You can use individual service endpoints such as Outlook REST API if you need a feature that is only available in the individual service endpoint, either in production (v2.0) or as preview (beta).