Governance on Lamden is the way which the blockchain modifies itself. This is done by a process of voting of different variables in state that then modify the behavior of the system. This behavior modification can be in the core protocol, or above in just the smart contracting protocol.
We call each of these things you can vote on policies. Policies can be added to the system dynamically and will generally be introduced to the protocol layer with an upgrade (also a policy).
There is a single master contract called
election_house that is set in state on default. It provides the singular API for interacting with all of the official Lamden governance policies. Notice that this is only for the policy that affects the core protocol, so popular voting on delegates and masternodes is not done in the Election House.