This document provides a list of proofreading symbols and their meanings. It includes over 30 symbols such as delete, insert, lowercase, new paragraph, and more. It also lists 10 rules of effective proofreading such as never proofreading your own work, reading backwards to catch spelling errors, taking breaks, and making legible marks. The symbols and rules are intended to help editors and proofreaders clearly communicate changes that need to be made to documents to eliminate errors.