Mechanization refers to the use of powered machinery to help a human operator in some task. The use of hand-powered tools is not an example of mechanization. The term is most often used in industry. The addition of powered machine tools; such as the steam powered lathe dramatically reduced the amount of time needed to carry out various tasks, and improves productivity. Today very little construction of any sort is carried out with hand tools. Automation and mechanization are often confused with each other, though it should not be too hard to keep them apart. Mechanization saves the use of human muscles; automation saves the use of human judgment. Mechanization displaces physical labor, whereas automation displaces mental labor.
Mechanization is the replacement of human power by machine power. Mechanization often replaces craftwork and creates jobs for unskilled labor. It also only affects one or two industries at a time. Mechanization moves slowly and the job displacement is short-term. Mechanization is what occurred during the industrial revolution. Automation is the replacement of human thinking with computers and machines. Automation tends to create jobs for skilled workers at the expense of unskilled and semi-skilled workers. It affects many industries at the same time, moving rapidly. It also creates longer-term job displacement and has been more characteristic since the 1950s.