My sister called me the other night to ask about the phrase, “two bits.” It is a phrase that I don’t hear much anymore, but people of my father’s generation used it all the time to refer to a quarter of a dollar. It seems kind of strange for us to use because one “bit” would be twelve and a half cents. So what’s up with that?
It all goes back to another curious phrase, “pieces of eight.” From the mid-14th century for a few hundred years, the Spanish dollar was worth 8 reals. So a piece of eight was a silver coin worth one dollar or eight reals.
Similarly, since the dollar was divided into 8 reals, 1 real (or bit) is worth 12.5% of a dollar. Thus two bits is a quarter.
Now if we could just understand the basis of “mind your Ps and Qs“!
I suspect "mind your Ps and Qs" refers to the very slight difference, when writing longhand, between a lower case p and a lower case q. Basically, "Pay attention to what you’re doing." Not sure why it isn’t "Mind your Ds and Bs" or "Mind your Gs and Qs".