The Man who saved Millions, Edward Jenner
What has this man done for humanity well you might know him for one of the greatest inventions, Vaccines!, In 1796 he had developed and inoculated a 13 year-old-boy Who had “Vaccinia” (Aka Cowpox) by doing so he had cured them of Cowpox.
He did not stop there however he had developed the first Smallpox vaccine in 1798, and through out the rest of the 1700s and 1800s he had spent that time to systematic implementation of his cure of Smallpox all around the world, and by 1979 Smallpox has been completely eradication all because Of this man
One of the most important things that he has done is he did all of this for free none of this was done for profit And by doing all of this he has save so many innocent souls.
Sources: http://www.immune.org.nz/vaccines/vaccine-development/brief-history-vaccination