Azure Active Directory

docs.microsoft.com
Azure Active Directory - Link

Microsoft Tech Community -
Azure Active Directory - Link

Official Blog
Azure AD - Link

What's New -
Azure Active Directory - Link

Azure Active Directory Comparison - Link

Azure Active Directory - Introduction (Wiki) - Link

Configuring Alternate Login ID - Link
When your UPN can't match the user login ID.

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Azure AD Premium P1
Included in E3 Enterprise Mobility + Security


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Azure AD Premium P2
Included in E5 Enterprise Mobility + Security


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