The most significant technological development that has had the most profound impact on how people live, making life different than it was in the Victorian era.

The most significant technological development was the development of the steam engine and the use of electricity.

Explanation:

The development of the steam engine started the first industrial revolution and was one of the foundations of capitalism. Through this technology, several factories were developed that were able to produce products on a large scale, quickly and at lower prices. In addition, factories provided many job openings, allowing many people to migrate from rural areas to cities, promoting an extension of cities and population growth.

Electricity was also a major technological advance, allowing people to do their activities at night, optimizing work and promoting an improvement in life.

in our power to make a world happy - to teach mankind the art of being so - to a character hitherto unknown - and to have, as it were, a new creation intrusted to our hands, are honors that command reflection, and can neither be too highly estimated,