https://www.britannica.com/topic/Armada-Spanish-naval-fleet - Encyclopedia Britannica article covering the Spanish Armada. It gives the background to the incident, a discussion of both fleets, and a discussion of the Spanish defeat.
http://users.clas.ufl.edu/ufhatch/pages/03-Sci-Rev/SCI-REV-Teaching/03sr-definition-concept.htm - This write-up comes from Dr. Robert A. Hatch from the University of Florida. Hatch tackles The Scientific Revolution, what is generally marked as its beginning and end points, along with why it is significant in history.
https://www.youtube.com/watch?v=YMpfdpHPNDE – Video from NowThis World summarizes the Ottoman Empire, it explains why the empire is so significant today, their vast territorial claims, and their downfall.
https://www.youtube.com/watch?v=IATyzSAjC1w – This National Geographic video explains the Protestant Reformation in Europe, Martin Luther and his impact on the split from the Catholic Church.