The comma , form the Greek κόμμα komma, is a punctuation mark, and it appears in several variants in various languages. It has the same shape as an apostrophe or single closing quotation mark in many typefaces, but it differs from them in being placed on the baseline of the text. Some render it as a small line, slightly curved or straight but inclined from the vertical, or with the appearance of a small, filled-in number 9. It is used to separate parts of a sentence such as and lists of three or mo..
