Overview of Microsoft Graph

Microsoft Graph is the gateway to data and intelligence in Microsoft 365. It provides a unified programmability model that you can use to access the tremendous amount of data in Microsoft 365, Windows, and Enterprise Mobility + Security.

Microsoft Graph exposes REST APIs and client libraries to access data on the following Microsoft cloud services:

-Microsoft 365 core services: Bookings, Excel, Microsoft 365 compliance eDiscovery, Microsoft Search, OneDrive, OneNote, Outlook/Exchange, People (Outlook contacts), Planner, SharePoint, Teams
-Enterprise Mobility + Security services: Advanced Threat Analytics, Advanced Threat Protection, Azure Active Directory, Identity Manager, and Intune
-Windows services: activities, devices, notifications, Universal Print
-Dynamics 365 Business Central services

What’s in Microsoft Graph API?
The Microsoft Graph API is a RESTful web API that enables you to access Microsoft Cloud service resources. After you register your app and get authentication tokens for a user or service, you can make requests to the Microsoft Graph API.

In the Microsoft 365 platform, three main components facilitate the access and flow of data:
1.Microsoft Graph API
2.Microsoft Graph connectors
3.Microsoft Graph Data Connect (Tools)

Popular API request
Operation URL
GET my profile https://graph.microsoft.com/v1.0/me
GET my files https://graph.microsoft.com/v1.0/me/drive/root/children

https://developer.microsoft.com/en-us/graph/graph-explorer

Courtesy : https://learn.microsoft.com/en-us/graph/overview