Question

What new innovations changed life in the United States?

Answer 1

Roads, waterways, railroads, steam boats, and refrigerator railroad cars.

Answer 2

One of my favorites as @Jakelee mentioned are waterways. IE; Canals and navigation are human-made channels for water. In the vernacular both are referred to as 'canals'. The main difference between them is that a navigation parallels a river and shares its drainage basin, while a canal cuts across a drainage divide.