The Wheel is the single greatest invention. It lead to faster travel time, and other great inventions. Its like a gigantic pyramid, going down from the wheel
I would say 1. Wheel 2. Electricity 3. Computer 4. Industrialization 5. Guns Greatest meaning largest impact on the world Computer has had the largest impact on the world after Electricity and the Wheel. Without the computer, the world would be incomprehensibly different.
Greatest inventions would be the World Wide Web, Mobile Phones or bank cards. Money controls this world, and bank cards control alot of money