The document provides definitions and examples to distinguish between abbreviations and acronyms. An abbreviation is a shortened form of a name or term, such as "postop" for "postoperative". An acronym is an abbreviation formed from the initial letters of a term, such as "FBI" for "Federal Bureau of Investigation". All acronyms are abbreviations, but not all abbreviations are acronyms. Historically, acronyms formed pronounceable words, but recently acronyms have been formed without consideration of pronunciation. The document then provides guidelines for formatting a list of abbreviations in a document.