DeWalt is an American worldwide brand of power tools and hand tools for the construction, manufacturing and woodworking industries. this company is a trade name of Black & Decker (U.S.) Inc., a subsidiary of Stanley Black & Decker.
The original company was started in 1923 by Raymond E. DeWalt, the inventor of the radial arm saw. The company grew quickly and was reorganized and re incorporated in 1947 as DeWalt Inc. After buying the company in 1949, American Machine & Foundry Co., Inc. sold it to Black & Decker in 1960. Black & Decker divested itself of the radial arm saw manufacturing branch in 1989, selling it to two executives.
In 1992, Black & Decker started a major effort to rebrand its professional quality and high end power tools to DeWalt. Currently, DeWalt manufactures and sells more than 200 different power hand tools and 800 accessories. In 1994, DeWalt took over the German wood working power tool producer ELU.
On September 1, 2016, this company debuted an industry first hybrid voltage battery pack it branded “FLEXVOLT”. The pack runs at either 20V (18V nominal) or 60V (54V nominal) depending upon whether it is placed into a 60V FlexVolt tool or one of their 20V Max tools. The pack switches between connecting the battery cells in series (60V, 2Ah) or parallel (20V, 6Ah) depending upon the activated pin configuration determined by the power tool. 
In May 2018, Dewalt released a line of cordless lawn mowers, that uses either their 20v or 40v batteries.