It was the use of steam engines, invented by two people, James Watt and Thomas Newcomen. It was a way to power specific machines without relying on too many natural resources. These industrialized factories enabled transportation by train.
A steam engine requires a fuel source, such as coal or wood, to heat water and produce steam. This will create steam and activate the engine. This also needed air to allow the fuel to heat up. Most steam engines are made of metal for durability and to absorb heat.
It enabled the factory system, which allowed multiple people to work on a machine simultaneously. This significantly decreases the time required to produce just one thing. It allowed for a more efficient way of making things and fewer resources to be used.
Factories are similar to mills as they both manufacture goods at a faster rate than handcrafted goods. However, they differ in many ways, as mills are a method for breaking things down into smaller pieces, while factories are a sequential process for completing a product. Factories produce different products from mills, as they manufacture cars and heavier goods, whereas mills focus on creating more lumber and textiles.
Factories today are mostly powered by electricity from solar power or other grids. They also utilize other sources of energy, such as natural gas and renewable fossil fuels. They combine many types of fuels to make everything faster and efficient.
Steam power is still used today to generate electricity in power plants. It also helps generate energy for chemical plants and other things. It benefits many urban areas as it can be used for medical equipment or special trains. In many ways, it is still used today for small things around the city.