From wikipedia, so take it or leave it..
http://en.wikipedia.org/wiki/Henry_F._PhillipsPhillips head screws are " purpose made to cam out when the screw stalled, to prevent the fastener damaging the work or the head, instead damaging the driver. This was due to the relative difficulty in building torque limiting into the early drivers. "
Reed & Prince or Frearson
Similar to a Phillips but has a more pointed 75° V shape.[citation needed] Its advantage over the Phillips drive is that one driver or bit fits all screw sizes. It is found mainly in marine hardware and requires a special screw driver or bit to work properly.
The tool recess is a perfect cross, unlike the Phillips head, which is designed to cam out. It was developed by an English inventor named Frearson in the 19th century and produced from the late 1930s to the mid-1970s by the former Reed & Prince Manufacturing Company of Worcester, Massachusetts, a company which traces its origins to Kingston, Massachusetts, in 1882, and was liquidated in 1990 with the sale of company assets. The company is now in business.
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