Punctuation

Q. I was hoping you could tell me if brackets can be used instead of parentheses for most things. For example, HG Blending Salt without any additives (P7-726) and HG Blending Salt (P7-727) with an additive. Could I use brackets instead?

A. Conventional usage calls for parentheses. Brackets have other uses: they can set off a parenthesis within a parenthesis (like this [and this]), and they can indicate words that the writer or editor is inserting into text written by someone else. So if parentheses will do, it’s probably not a good idea to use brackets instead.

[This answer relies on the 17th edition of CMOS (2017) unless otherwise noted.]