What Is The Difference Between An Azure Tenent, Azure Directory and Azure Active Directory?

Question

Following on from this question, I don't understand what the difference between an Azure Tenant, Azure Directory and Azure Active Directory.

When I log in to Azure and click my profile it lets me Switch Directory.

In my case I can switch to my company directory and also to the directory of another company where I have guest credits.

Does Directory in this context mean the same as Azure Active Directory?

The documentation says a tenant is:

Azure tenant: A dedicated and trusted instance of Azure AD that's automatically created when your organization signs up for a Microsoft cloud service subscription, such as Microsoft Azure, Microsoft Intune, or Office 365. An Azure tenant represents a single organization.

So is Tenant the same as Directory in this case as well?

Answer 1

Directory == Tenant.

When you utilize azure services, the TenantId will be requested. The TenantId is non other than the DirectoryId which can be found in the Properties tab within Azure Active Directory.

Furthermore, as answered in the link you provided:

"Subscriptions are tied to tenants. so 1 tenant can have many subscriptions, but not vice versa."

Azure Active Directory is Microsoft’s cloud-based identity and access management service, which helps your employees sign in and access resources

Answer 2

Yes, in this case the tenant is the same as an Azure AD. In the Azure portal you are changing Azure Active Directories when you use the Switch Directory feature. You can currently only be in the context of a single directory at a time; however, as the previous question you pointed to indicates, multiple subscriptions can be tied to a tenant/directory. So when you are in the context of a directory you'll see all the subscriptions under that tenant to which you have access to one or more resources based on security.

To be fair, I use Azure AD Tenant/Azure AD Directory interchangeably. The Portal UI calls them directories; however, the properties on resources, REST APIs, CLI commands, etc. all refer to it as a tenant.