Manuscript Mark is a term used in the editing and proofreading process. It refers to the marks made on a document to indicate changes or corrections that need to be made. The most common marks are STET, DELE, and ITAL. STET stands for 'let it stand, ' meaning that the editor or proofreader has decided not to make any changes to the text. DELE stands for 'DELETE, ' indicating that the editor or proofreader wants the text to be removed. ITAL stands for 'ITALICIZE, ' meaning that the editor or proofreader wants the text to be italicized.