The distinguished engineer Owen Williams, of the early 1900's, described it well when he said "the factory building is the shell surrounding a process". I believe that without factories, the Industrial Revolution most likely would have never happened.
In the 1800’s the factories were powered by steam or water power transmited by overhead shafts and belts, and were lit by natural gas lights.
Then in 1880, Thomas Edison developed the incandescent electric light, and by 1885 his electric lighting system had started to catch on. Electric power of machinery started to take off at about the same time.
The beginning of the 20th century is seen as a period of industrial expansion in the United States. The Westinghouse factories in the US were considered to be among the most modern factories of their time with the best working conditions.
Most women that worked in these factories during that time performed repetitious assembly tasks with men doing the “skilled labor”.
As the 20th century has moved along we have seen innovations like the assembly line and computer automation, and improvements to safety and working conditions like powerful overhead lights and safety guards on machines. These days you will find factories manufacturing everything from flutes to Boeing 747’s. We can only wait and see what the 21st century will bring us.