The Stack is at the core of Planet Nine. It is a set of five, open source, protocols that allow for users to engage with Planet Nine things. Since stacks go from the bottom up, this next paragraph is the top of the stack.
The Adversement (coming soon) - The protocol for businesses to interact with users in The Advancement.
The Advancement 
- The vanguard of Planet Nine, battling the scourge that is advertising.
Teleportation - The protocol for transporting rich content from somewhere on the web to somewhere else.
MAGIC - Multi-device Asynchronous Generic Input/output Consensus: it's how Planet Nine does its magic.
Sessionless - The auth protocol that provides discardable identities for Planet Nine