Comma

The comma ( , ) is a punctuation mark. 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 typefaces render it as a small line, slightly curved or straight, or with the appearance of a small filled-in number 9. The comma is used in many contexts and languages, principally for separating things. According to the Oxford English Dictiona... more

The comma ( , ) is a punctuation mark. 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 typefaces render it as a small line, slightly curved or straight, or with the appearance of a small filled-in number 9. The comma is used in many contexts and languages, principally for separating things. According to the Oxford English Dictionary, the word comma comes directly from the Greek komma (κόμμα), which means something cut off or a short clause. In the 3rd century BC, Aristophanes of Byzantium invented a system of single dots (distinctiones) that separated verses (colometry) and indicated the amount of breath needed to complete each fragment of text when reading aloud (not to comply with rules of grammar, which were not applied to punctuation marks until much later). The different lengths were signified by a dot at the bottom, middle, or top of the line. For a short passage... less