This is the first part of what is planned as a multi-part discussion on middle knowledge and free will. This part discusses the fact that God's knowledge is intrinsically simple (undivided) but can be divided extrinsically (as to its objects) into two categories: natural and free. These two categories exhaust all the objects of God's knowledge.
To summarize what I've put in the video, the following are the main points:
1) God's knowledge is, in and of itself, simple and undivided.
2) God's knowledge can be, however, considered by us (theologians) in relation to its objects as either natural or free.
3) Natural Knowledge is God's knowledge of the extent of his own power without considering how God plans to exercise this power. Thus, God knows what God could do, if God so chose to do it. He knows every way that he could exercise his own power, if he wished to exercise it.
4) Free Knowledge is God's knowledge of the actual exercise of his power. That is to say, Free Knowledge is God's knowledge about the world that he has made and the history that he has brought into being, as well as the future that remains to be seen.