The Rockefelers improved the world with an infinite number of valuable investments.  Some of the many investments that were made supported areas such as: The Arts, religion, medicine, military, etc.  The Rockefellers improved the world by supporting these various philanthropies.  The philanthropies had a very large effect on the population. It was because of the Rockefellers that hookworm was eradicated from the world.  The Rockefellers built a university in 1901, a university for medicine and science.  They also donated towards causes like missions, hospitals, and many other Medical Schools.  And last but not least religion.  John D Rockefeller gave millions to his Church, Baptist.