screw: Quick Facts

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Photos and Videos

Illustration showing seven types of screws and screw heads in a row, including a cap screw, machine screw with oval head, setscrew with hollow head, self-tapping screw, flat-head wood screw, machine screw with Phillips head, and lag screw, each labeled beneath.

A diagram displays six types of simple machines with labeled illustrations: inclined plane, wedge, screw, lever, wheel and axle, and pulley, each shown with real-world examples like ramps, axes, screws, seesaws, door handles, and pulleys lifting objects.

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Topics

lag screw machine screw power screw wood screw screw thread cap screw setscrew self-tapping screw Archimedes screw screw fastener spring wheel and axle flywheel brake lever bearing clutch shaft coupling governor pulley

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Key People

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William Sellers

American engineer and manufacturer