What is the common name for the punctuation mark “,”? It is called a comma. The comma is used to separate parts of a sentence, clauses, phrases, or items in a list, although its exact rules vary among languages and style traditions.
The word comes from the Greek komma, meaning a piece cut off or a short clause. The punctuation concept reaches back to the system of marks associated with Aristophanes of Byzantium in the third century BC. The modern comma developed from earlier slash-like marks used to indicate pauses and was standardized in printing associated with Aldus Manutius.
A comma is not simply a written pause: inserting or removing one can change meaning, as in “Let’s eat, Grandma” versus “Let’s eat Grandma.” The mark also appears in specialized forms, including the Oxford comma, which separates the final two items in some lists. In computing, the same character can delimit fields or function arguments, and in Unicode the ordinary comma is character U+002C.