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9. Style Guides

When to Use Which Style Guide

Style Guide When to Use
The Chicago Manual of Style (CMOS) most common style guide, many other style guides reference back to it, used in publishing, academic books, and journals
The Associated Press Stylebook (AP) used by journalists and other news and media writers
Institute of Electrical & Electronics Engineers Style Manual (IEEE) used in engineering and computer science
The American Medical Association Manual of Style (AMA) used in nursing and other medical fields
The Association for Computing Machinery Style Guide (ACM) used in computing and information technology fields
The American Society of Mechanical Engineers (ASME) used in mechanical engineering
Modern Language Association (MLA) the "college predecessor" to Chicago, used in academic writing in humanities and literary fields
American Psychological Association (APA) the "college predecessor" to AP, used in academic writing in the education, psychology, and science fields
Turabian a brief, student version of Chicago, used in academic writing in business, history, and fine arts fields

Style Guide Treatment of Numbers

Style Guide Treatment of Numbers
The Chicago Manual of Style (CMOS) spell out whole/round/simple numbers (two hundred)



use numerals for complex numbers (223)
The Associated Press Stylebook (AP) spell out numbers one through nine (one, two, three . . . nine)



use numerals for numbers 10 and greater (10, 11, 12 . . .)
Institute of Electrical & Electronics Engineers Style Manual (IEEE) n/a
The American Medical Association Manual of Style (AMA) use numerals for all numbers (1, 2, 3 . . .)



use a space between the number and unit and don't use a period (16 mg)



no commas in longer numbers (1600, 23000)
The Association for Computing Machinery Style Guide (ACM) n/a
The American Society of Mechanical Engineers (ASME) n/a
Modern Language Association (MLA) same as Chicago
American Psychological Association (APA) same as AP
Turabian same as Chicago