Here is my quick summary.
Our servers and/or gateways do it all. IPv4/IPv6
If you communicate in IPv6, go for it. Otherwise, IPv4 is okay too.
Tunneling: (kind of like VPN tunneling)
****, I have IPv6. Our remote office has IPv6.
But I need to jump this IPv4 puddle, so we can communicate in IPv6.
Hey, I know. I will tunnel over it.
NAT: (true translation of one to the other - vice versa)
Let's just get along, and translate into the IP standard on the other side.
*same as private IPs to public IPs (NAT)
Here are some practice session at GNS3VAULT.com
NAT-PT is a method for IPv6-only hosts to communicate with IPv4-only hosts. Dual stack and the various forms of tunneling don't do any protocol translation, so even with those methods of IPv6 transition hosts must use IPv4 to talk to other IPv4 nodes and IPv6 to talk to other IPv6 nodes. You need a method of protocol translation like NAT-PT or NAT64/DNS64 for an IPv6-only node to talk to an IPv4-only node.
Officially NAT-PT is deprecated by RFC4966 and is not a recommended transition mechanism, but it's still possible to configure and use it in your network. NAT64/DNS64 is now the preferred translation method.
There are lots of methods... As El Tigre summarizes, that's what I'd concentrate on for the tests.
Yes, Bradford, NAT-PT is deprecated, and we'll see quite a lot of movement as people finally start deploying 15-year old technologies as something new. However, the exams aren't quite that detailed, and they don't quite keep up with the latest and greatest in the standards anyway.
How many years after site-local addresses were deprecated did those things still get taught?