A "machine tool" is a machine which makes parts to other machines, such as screws or gun stocks, generally without a skilled craftsman doing the precision work. Instead, a machine operator controls the machine as it does the precision work. Lathes, milling machines, and drill presses are precision machine tools. The museum has the largest collection of historically significant machine tools in the United States. The museum's holdings include a collection of industrial machinery spanning the first one hundred years of precision manufacturing, along with fine examples of early machined products including rifles, sewing machines, and typewriters. Photographs and archival records provide additional resources for interpreting this critical phase of the Industrial Revolution.