What is comma?
The comma is the workhorse of English punctuation, signaling a short pause inside a sentence. It separates items in a list ("red, white and blue"), sets off parenthetical asides ("the feature, built for speed, ships today") and divides independent clauses joined by a conjunction ("We shipped the feature, and the team celebrated"). Placement affects meaning as much as rhythm.
In a list: We ship marketing, product and support copy.
Parenthetical aside: The feature, built for speed, ships today.
Joining clauses: We shipped the feature, and the team celebrated.
Why does comma matter?
Commas shape how a reader experiences pace, and they can change meaning entirely. "Let's eat, Grandma" and "Let's eat Grandma" are the canonical example, but subtler shifts happen in brand copy every day. A consistent approach to commas, especially around lists and parenthetical clauses, makes writing feel deliberate. An inconsistent one makes even strong prose feel patchy.
How do you use comma?
Decide whether your brand uses the Oxford comma, and apply the rule the same way across every surface.
Use commas to set off parenthetical asides and trailing breaks rather than relying on em dashes, which carry more dramatic weight.
Avoid the comma splice: do not join two independent clauses with a comma alone, since the result reads as a run-on.
