The Humble Screw Has Changed Direction Only Once in History

Wood screws were designed to be turned clockwise to tighten for centuries. The standard was established by Henry Maudslay's screw-cutting lathe in the early 1800s and has remained unchanged. Left-handed threads exist for specific applications — like bicycle pedals on the left side, where regular pedalling would loosen a standard thread.

Source: The Measure of Reality — Alfred Crosby