Letters, memos and e-mail come up in everyday written communication situations and may be formal or informal based on the audience and purpose. "Letters are typically used for correspondence outside an organization. Memorandums (or memos) are used for correspondence within an organization" (Pearsall & Cook, 2010, p. 145).
Pearsall, & Cargile Cook. (2010). The elements of technical writing (3rd ed.). New York: Longman.
This sample is from the Free Online Textbook for Technical Writing provided and maintained by David McMurrey.
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