This document discusses different types of business letters. It describes business letters as letters between companies or organizations and their customers or clients. There are various types of business letters, including order letters, adjustment letters, complaint letters, letters of recommendation, and letters of resignation. The document also outlines the typical components of a business letter, including the letterhead, return address, dateline, letter address, salutation, body, complimentary close, signature, keyed name, and typist initials. Finally, it provides an example of a block format business letter.