What is the relationship between James Madison, The Articles of Confederation, and The Federalist papers?

What is the relationship between James Madison, The Articles of Confederation, and The Federalist papers? Thanks guys im reviewing for exam and this answer would really really help me understand it thanks. Answer doesn't have to be long just about 6 sentences is long enough i would say for me to understand this but if you think you need to say more go ahead. Thanks in advance!!!!