Henry F. Phillips invented both the screw and the driver that bear his name. The Oregon businessman patented two versions of a fastening device for crosshead screws in 1934 and 1936. Phillips intended the screw for use with automatic screwdrivers and marketed it for mass-production industries such as auto manufacturing.
The Phillips screw can be driven with more torque and holds better than slotted screws. The Phillips system is also self-centering. If you press the tip of the screwdriver against the screw head, it takes only a little wiggling to seat it properly. The speed with which Phillips screws can be used was crucial to the auto assembly line. In addition, Phillips screws are almost impossible to over screw, which was also very important for industry.
Phillips persuaded the American Screw Company to manufacture his screw design, and the company convinced General Motors to use the screw on the 1936 Cadillac. By 1940, most American automakers used Phillips screws. When the U.S. needed to crank out jeeps and tanks for World War II, Phillips screws were an essential component in the war effort.
Interestingly enough, Phillips was not the first to improve on the old slotted screw. In 1908, Canadian Peter L. Robertson invented a square-head screw. The Robertson screw was the first recess-drive fastener that was practical for mass production. It had all the advantages of the Phillips, but Robertson was unable to get it used by American industries. This screw is standard in Canada and is favored by woodworkers on both sides of the border.