Slide rules seem very anachronistic but this is only because of the their form but not their purpose. They are low-tech, continuous (vs. discrete, as in "table

Slide rules seem very anachronistic but this is only because of the their form but not their purpose. They are low-tech, continuous (vs. discrete, as in "tables with values in a booklet") lookup "tables" for functions that would have been too time-consuming (or error-prone?) to compute at "runtime". And they even allow parameters to be taken into account. These things are absolutely ingenious inventions.