Why do even the simplest calculators feature a square root key?

[Egan Ford]

(05-07-2018 01:06 PM)Accutron Wrote:  By the early 1980s, square root had become a value-added feature with a negligible production cost increase, and was simply included to avoid losing a sale to another calculator with square root.

This was my thought as well. If your competitors have it, then you need it. If your competitors do not have it, you still need it to differentiate (recognize or ascertain what makes (someone or something) different, not that other kind :-).