Caret

It marks where an editor should insert missing text. In proofreading, the proofreader places ‸ in the line and writes the missing word or passage in the margin. This insertion mark links the gap to the proposed addition.

The English word “caret” is traced to the seventeenth century; that dates the word, not necessarily the mark. The familiar keyboard ^ has its own history: typewriters used it to overprint a circumflex accent, and computers later used it in programming and mathematics.