What is a staging table and how do you protect data loss when transferring the data?
I believe I have a basic understanding of what a staging table is.
  From my understanding it is just a location to temporarily store data
  before moving that data to its permanent home.


Yes, it is.


  To my knowledge you can't perform this type of operation on a table
  with enabled triggers(used to add a sequenced primary key).


This is a restriction of direct path load, not staging tables.

Direct Path Loads, Integrity Constraints, and Triggers

Triggers fire during conventional path loads.


  How do you protect data loss when transferring data from a staging
  table to it's permanent home(permanent table?)


You don't. Direct path loads do not generate the redo that would make possible recovering the data affected by it in case of a recovery situation (this is to improve performance). Since it is just a temporary location, if it is damaged or lost, you can just start over and repeat the loading process.

If you want it to be protected, then use conventional path load.