Square brackets
Square brackets are paired punctuation marks ([ ]) used to insert editorial notes, clarifications or substitutions inside quoted or technical material.
Also known as:
Brackets
What are square brackets?
Square brackets are a pair of upright punctuation marks used to insert something into otherwise untouched text. You see them most often inside direct quotes, where an editor clarifies a pronoun or tweaks a verb tense to fit the new sentence: "She said it [the feature] launched on Tuesday." They also mark omitted words in a quote ("[...]") and stand in for variables in technical writing that a reader is meant to replace.
Clarification in a quote: "She said it [the feature] launched on Tuesday."
Omission: "The report found [...] no material change in usage."
Placeholder: Reply to [customer name] within 24 hours.
Why do square brackets matter?
Square brackets are the signal that a writer has touched someone else's words, which is why they carry so much weight in quoted material. Skip them, and a small rewrite of a direct quote reads as a misquote. In product and marketing copy, brackets serve a different purpose: they flag every place a template needs a real value before shipping, which makes them a useful guardrail against sending a draft with "[customer name]" still visible.
How do you use square brackets?
Use square brackets to insert a clarification, substitution or omission inside a direct quote without misrepresenting the speaker.
Use square brackets, not parentheses, for editorial interventions, since parentheses suggest the original author added the aside.
Treat brackets as placeholder markers in templates and always run a final check for stray brackets before publishing anything.
