Difference between REST API and Graph API for Azure.

[KoKyi]

I am learning APIs of Azure. I found that there are two API for Azure, Normal Rest API and Graph API. 

Can someone tell me why there are two APIs?

I also found that there is no azure ad user creation API in Normal Rest API. But Graph API has. This is one thing I find out about differences in these two API. Is my finding correct? 

[#2]

There are many REST APIs in Azure ;) , but I think you are referring to Azure Resource Manager (ARM) API as "normal Rest API' and Microsoft Graph API for accessing many M365 resources in a unified way, including Azure Active Directory objects.

In other words, you use ARM API to manage Azure resources, and MS Graph API to manage AAD objects (users, groups, etc.).

[#3]

@David Pazdera Thanks. I get it.