It’s pretty damn hard to pick just one thing, so my best-of list
There’s really basic foundational things like the wheel, cutting tools, fire (if we want to count it as an invention,) string/rope/cordage, writing, clothing, cooking, agriculture, metalworking, etc. the sort of things that are absolutely basic building blocks of civilization.
Moving a few milenia up, and in no particular order,
the Haber Process to synthesize ammonia, which allowed for the creation of synthetic fertilizers. If you’ve eaten any commercially grown food in the last century, you probably owe it to the Haber Process.
Antibiotics are another big one, as are vaccines.
Vaucason’s lathe arguably laid the foundation for a whole lot of fabrication techniques that led to the industrial revolution
Refrigeration
Steam engines and later internal combustion engines
It’s pretty damn hard to pick just one thing, so my best-of list
There’s really basic foundational things like the wheel, cutting tools, fire (if we want to count it as an invention,) string/rope/cordage, writing, clothing, cooking, agriculture, metalworking, etc. the sort of things that are absolutely basic building blocks of civilization.
Moving a few milenia up, and in no particular order,
the Haber Process to synthesize ammonia, which allowed for the creation of synthetic fertilizers. If you’ve eaten any commercially grown food in the last century, you probably owe it to the Haber Process.
Antibiotics are another big one, as are vaccines.
Vaucason’s lathe arguably laid the foundation for a whole lot of fabrication techniques that led to the industrial revolution
Refrigeration
Steam engines and later internal combustion engines
Clocks
Compasses
Printing press
The telephone
Airplanes
Computers and the internet
Cameras
Refrigeration is my favourite on your list. Without it, there’s no lager.
Also it’s the one my parents talk about. They used to go out everyday and pluck food from the ground. Every day.
Fridge changed that overnight. Suddenly people had time to do other things (mostly chat with their friends in cafés)
The industrial revolution was the biggest double edged sword ever!
The washing machine was probably the next big time saver. Now we spend all our free time on the internet…