This document provides guidance on writing different types of business correspondence, including memos, emails, and letters. It discusses key differences between these formats and how to determine the purpose and audience. For each format, it outlines the essential components and provides tips. For example, it recommends including a clear subject line in memos and emails to help readers understand the focus. It also provides examples of introductions, discussions, and conclusions for different letter types like inquiries, covers, and sales. The document aims to help readers properly structure and write effective business communications.