Yes, I knew about both of them (dc and bc) from before, having worked on Unixen for years.

And have used bc a lot.

Check out the useful bc -l option.

Here is the page for bc:

https://en.m.wikipedia.org/wiki/Bc_(programming_language)

which is mentioned in the dc page's See Also section, which is what I alluded to in my earlier comment above, i.e. that bc is built on dc.

See the History section of the bc page.