Editing Mechanization (section)

===Powered machinery===
{{see also|Mass production}}

Powered machinery today usually means either by electric motor or internal combustion engine.  Before the first decade of the 20th century powered usually meant by steam engine, water or wind.

Many of the early machines and machine tools were hand powered, but most changed over to water or steam power by the early 19th century.

Before [[electrification]], mill and factory power was usually transmitted using a [[line shaft]].  Electrification allowed individual machines to each be powered by a separate motor in what is called ''unit drive''.  Unit drive allowed factories to be better arranged and allowed different machines to run at different speeds.  Unit drive also allowed much higher speeds, which was especially important for [[machine tools]].<ref>Bartelt, Terry. Industrial Automated Systems: Instrumentation and Motion Control. Cengage Learning, 2010.</ref>

A step beyond mechanization is [[automation]].  Early production machinery, such as the glass bottle blowing machine (ca. 1890s), required a lot of operator involvement.  By the 1920s fully automatic machines, which required much less operator attention, were being used.<ref name="Jerome 1934">{{Cite book | last1=Jerome | first1=Harry| title=Mechanization in Industry, National Bureau of Economic Research | year=1934 | url=https://www.nber.org/chapters/c5238.pdf }}</ref>