Under all of the components within the administration portal, there are a number of additional portals for administering specific services, under the expandable heading Admin centers:
Admin centers
It's outside the scope of this chapter to go into any detail regarding those administrative centers; most are covered within their own chapters. (Note that this screenshot comes from a tenant which also has Dynamics 365 and Intune; neither of those are within the scope of this book, as neither are technically a part of Office 365. Intune is part of Windows Azure, and Dynamics 365 is its own separate product. Azure AD, despite the name, is part of Office 365, as well as Azure.)