Answer:
Steam engine
Explanation:
The first steam engine was developed in the 1700s but was not that useful until James Watt from Scotland designs a more efficient steam engine. The proved to be the most important invention of the industrial revolution.
Steam engines go on to power the first steam trains, steam boats and factories.
Other inventions like the sewing machine and the telegraph was important inventions which changed the lifestyle of people. People became more reliant on machines.
