https://docs.microsoft.com/en-us/windows/win32/ad/core-concepts-of-active-directory-domain-services

The following topics are core concepts of Active Directory Domain Services:

• Attributes
• Containers and Leaves
• Object Names and Identities
• Naming Contexts and Directory Partitions
• Domain Trees
• Forests
• Active Directory Servers and Dynamic DNS
• Replication and Data Integrity

https://docs.microsoft.com/en-us/windows/win32/ad/about-active-directory-domain-services

3. Labs (soon - looking for a good intro one)

4. Additional Resources: Everyone dig into this: https://docs.microsoft.com/en-us/learn/paths/active-directory-domain-services/ - let me know if you can access this, it is the Acitve Directory learning path from Microsoft

I can get in, but, I have tons of MS credentials. I'm curious what your experience.

Also: a few videos that I feel do a good job of setting the stage:

https://www.youtube.com/watch?v=3sFzqCr85Ks

https://www.youtube.com/watch?v=i9I5poSokow

https://www.youtube.com/watch?v=nKcrVtvZvpk