On Tue, 15 Feb 2022, Douglas McIlroy wrote:
First came "dc", an unlimited-precision desk
calculator,
which is still a Unix staple 45 years on. Building on dc,
she would later make "bc", which made unlimited precision
available in familiar programming-language notation and became
the interface of choice to dc.
In the form of GNU/NetBSD bc, I use bc(1) to this day as my tool of choice
for quick calculations.
-uso.