Those in the know advise us to use a screwdriver that fits perfectly into the slot in the screw. Because we got a chance to spend some time with expert recently, we learned why that's so important.

Phillips applied for his own patents in 1934 and '36. After years of rejection, he got the American Screw Company to spend $500,000 ($5.7 million in today's money) to develop a manufacturing process.

Phillips wasn't trying to make life with hand tools easier. He was trying to solve an industrial problem. To drive a slot screw, you need hand-eye coordination to line up the screwdriver and the slot.