Now, You're the DNS Master
DNS is one of those things that takes a lot of time to learn but isn't all that difficult to understand after you get past the basics. The big problem with DNS is that there is so much opportunity for error. It is easy to forget to modify a Host Address RR when a host changes its IP address. It is easy to forget to increment the zone serial number, in which case you might wind up scratching your head, wondering why the zone won't replicate to the secondaries. Take the time to experiment and test your results.
It is difficult to separate DNS and Active Directory. In fact, I had considerable trouble figuring out which to talk about first. Because DNS and Windows domains are merged under Active Directory, when you manage DNS, you're getting involved with Active Directory, and vice versa. Now you know enough about DNS to be able to plan the domain structure for your organization. The next task is to see specifically how DNS domains relate to Active Directory.