The most important invention in human history

My first choice is the steam engine. Mainly because that affected our Western concept of time , performance and availability. The steam engine was one of the inventions that led the industrial revolution and served as the basis for new transport technologies . Locomotive tracks bridging the east and west coasts has done wonders for our trade and industrialization of our country. This not only made the people and resources are available , but also created a new standard for time. Trains had to run the schedule and clock synchronization , working on the train schedule was a massive trickle-down effect on how people spent their daily activities . If you look at the mortality / fertility in industrialized countries before and after - the Industrial Revolution, the figures speak for themselves. The invention of the steam engine and the mechanization of the textile and new agricultural technologies , ultimately that increased life expectancy and reducing our fertility. The second embodiment is a vaccine. Just because I watched Boardwalk Empire last night and little Emily Schroeder was diagnosed with polio. - Oh and I also recently re- watched The Painted Veil and slow death through cholera Edward Norton. I am sooooo grateful to have a vaccine! Heather Fleming. It 's really hard to tell if there is one the most important invention in the history of mankind , because most inventions today are related to eachother . For thousands of years people have been trying to find more effective ways to improve life. Many inventions today are the results of inspiration from what people have done a long time ago . Unfortunately, I have not come up with one answer.