Looks like a typo! I probably wrote that back when there were only three types. But yes, there are five types, not three types.
I've made the change to the source document. In the next release, it should be fixed. I probably won't release a new version just to fix this typo – I try to keep the "noise" to a minimum and only release when there's something impactful to play.
But thanks for taking the time to bring it to my attention!