As far as I know, machine learning is part of artificial intelligence. The best source I can think of is Wikipedia. https://en.wikipedia.org/wiki/Artificial_intelligence

I have downloaded a number of courses on AI from The Pirate Bay (if you use it, beware of malware!), But I haven't followed them yet. In any case, the page I linked above seems very thorough. Take a look at it, and follow its sources. That should give you plenty to write about.