What we now recognize as pinball evolved in America during the 20th century, with several well-known companies leading the way.
Raymond Moloney founded the Bally Manufacturing Company in 1932 to make pinball games. Along with pinball, Bally fabricated mechanical slot machines and gambling devices. (During World War II, Bally halted production of recreational items and instead made ammunition and airplane parts.) The addition of flippers and bumpers transformed pinball from a gambling machine to a skill game. Bally purchased Midway Manufacturing Co., another amusements manufacturer, in 1969. Midway operated under its own name for another decade, until Bally merged its own pinball division with Midway’s to form Bally/Midway Manufacturing in 1981.
In 1943, Harry Williams founded Williams Manufacturing Company in Chicago, Illinois—the American center for pinball production. His company rose to prominence as one of the most important arcade and pinball game manufacturers in the United States after World War II. Williams pinball designers introduced many pinball innovations, including ramps, scoring reels, drop targets, and modern 3-inch flippers. The company was acquired and incorporated several times, resulting in company name changes (becoming Williams Electronics, Inc. in 1974 and WMS Industries in 1987).
In 1988, WMS purchased competitor Bally/Midway. The pinball division of WMS closed in 1999, after more than 50 years of designing and manufacturing electro-mechanical and solid-state pinball machines.