Nodes: Ops get all permissions default.
When you create your own Spawn Areas, they are assigned permissions under Spawn_Area.sa where the name is what you named it in config.yml. So if you made a Spawn Area called "forest," your permission would be Spawn_Area.sa.forest. The node Spawn_Area is not required for anything, but Spawn_Area.sa is required to use the /sa or /spawnarea command. Spawn_Area.sa.* lets the person you assign the permission to teleport to any of the Spawn Areas in your config.