What is ps and qs?

"Ps and Qs" is an expression that means to be careful or to pay attention to one's manners, behavior, or conduct. The phrase is often used to remind someone to be polite and attentive, especially in social situations. The origin of the phrase is uncertain, and there are a few theories about how it came into use:

1. Printing: One theory suggests that "Ps and Qs" originated in the printing industry. In the days of manual typesetting, letters were set in reverse. The lowercase 'p' and 'q' look similar and could be easily confused, so printers had to be careful to get them right to avoid printing errors.

2. Pints and Quarts: Another theory is that the expression comes from English pubs, where bartenders would keep track of customers' consumption of pints and quarts of ale. To "mind your Ps and Qs" was to watch the amount you drank and to ensure accurate accounts.

3. French Educational Phrase: It's also believed to possibly come from a French phrase 'pieds et queues,' referring to learning proper dance steps, where "ps" and "qs" could metaphorically remind someone of the feet formations required in dance.

4. Politeness and Grooming: Some suggest that it was a reference to children learning to form the letters correctly, and by extension, learning proper behavior.

Whichever the origin, the expression has been used for centuries to remind individuals to be careful and considerate in their actions and words.