There are many different style guides. Four of the most well-known are AP, MLA, Chicago, and Turabian. Different countries, schools, and companies have different rules for style. Some companies may not have any style preferences. These are the four most common professional and academic style guides in the United States. You can find some common style guides for the UK below.
1. APA (American Psychological Association)
The APA Style Guide, officially known as the Publication Manual of the American Psychological Association, is a widely used set of guidelines for writing and formatting academic papers. It’s particularly common in the social sciences, education, nursing, and other fields.
Key features:
- Citations: APA style provides detailed instructions on how to cite sources within your text (in-text citations) and how to create a comprehensive list of references at the end of your paper. This ensures proper credit is given to authors and helps avoid plagiarism. Â
- Formatting: This includes rules for page layout (margins, font, spacing), headings, tables, figures, and how to structure the overall paper (title page, abstract, introduction, methods, results, discussion, references). Â
- Writing style: The guide offers advice on clear and concise writing, including grammar, punctuation, and how to reduce bias in language. Â
Why is APA Style important?
- Clarity: It provides a consistent format that makes it easier for readers to understand and navigate academic papers. Â
- Credibility: Following APA style demonstrates that you’ve conducted your research thoroughly and are giving proper credit to sources. Â
- Professionalism: It’s the standard in many academic and professional settings, so familiarity with APA style is essential for success in these fields.
2. MLA (Modern Language Association)
The MLA Style Guide, officially known as the MLA Handbook, is a set of guidelines for writing and formatting academic papers in the humanities, particularly in fields like literature, languages, and cultural studies. It’s developed and maintained by the Modern Language Association.
Key features:
- Citations: It offers detailed instructions on how to cite sources within your text (in-text citations) and how to create a comprehensive list of works cited at the end of your paper. This ensures proper credit is given to authors and helps avoid plagiarism. Â
- Formatting: MLA style provides rules for page layout (margins, font, spacing), headings, and how to structure the overall paper. Â
- Writing style: The guide offers advice on clear and concise writing, including grammar, punctuation, and how to format quotations. Â
Why is MLA Style important?
- Clarity: It provides a consistent format that makes it easier for readers to understand and navigate academic papers in the humanities. Â
- Credibility: Following MLA style demonstrates that you’ve conducted your research thoroughly and are giving proper credit to sources. Â
- Professionalism: It’s the standard in many academic and professional settings within the humanities, so familiarity with MLA style is essential for success in these fields. Â

3. Chicago
The Chicago Style Guide, officially known as The Chicago Manual of Style, is a comprehensive guide to American English usage, grammar, punctuation, and citation. It’s published by the University of Chicago Press and is widely used in academic publishing, particularly in the humanities, social sciences, and history. Â
Key features:
- Citation: The manual provides two main citation systems:
- Author-date: This system uses in-text citations with the author’s last name and year of publication, with a references list at the end. Â
- Notes and bibliography: This system uses footnotes or endnotes to cite sources within the text, with a full bibliography at the end of the paper. Â
- Grammar and usage: Chicago offers detailed rules on grammar, punctuation, spelling, and style, helping writers produce clear and consistent prose. Â
- Indexing: Chicago offers guidance on creating indexes for books and other publications. Â
- Manuscript preparation: This includes guidelines on formatting your paper, from margins and font to headings and page numbers. Â
Why is Chicago Style important?
- Consistency: It provides a standardized set of rules that ensure consistency in writing and citation, making it easier for readers to understand and evaluate academic work. Â
- Clarity: Chicago emphasizes clear and concise writing, helping authors communicate their ideas effectively.
- Credibility: Following Chicago style demonstrates that you’ve conducted your research rigorously and are giving proper credit to your sources. Â
- Professionalism: It’s the standard in many academic and publishing settings, so familiarity with Chicago style is essential for success in these fields. Â
4. Turabian
The Turabian Style Guide is a set of writing and formatting guidelines primarily used by students and researchers writing papers, theses, and dissertations. It’s essentially a student-friendly version of the Chicago Manual of Style, offering a more streamlined approach to citation and formatting.
Key features:
- Author-date: This system uses in-text citations with the author’s last name and year of publication, with a references list at the end. Â
- Citation: Turabian outlines two main citation systems:
- Grammar and usage: Like Chicago, Turabian offers rules on grammar, punctuation, spelling, and style to help writers produce clear and consistent prose.
- Manuscript preparation: Turabian provides detailed guidance on formatting your paper, including margins, font, spacing, headings, and page numbers. It offers specific recommendations for structuring your paper, from the title page to the bibliography.
- Notes and bibliography: This system uses footnotes or endnotes to cite sources within the text, with a full bibliography at the end of the paper. Â
- Differences from Chicago: While closely based on Chicago, Turabian is tailored for students. It often provides more explicit instructions and examples for student papers, and it may offer slightly different formatting options
Why is Turabian Style important?
- Clarity and consistency: It provides a clear and consistent framework for writing academic papers, making them easier to read and understand. Â
- Credibility: Following Turabian style demonstrates that you’ve conducted your research thoroughly and are giving proper credit to your sources. Â
- Professionalism: It’s the standard in many academic settings, especially for student work, so familiarity with Turabian style is essential for academic success.
Which Style Should You Use?
The most important thing is to follow the instructions given by your instructor or the publication you’re submitting to. They will usually specify which style guide to use.
If you’re not given a preference, here’s a general guideline:
Choose based on discipline:
- AP for journalism or if you’re writing for a news outlet.
- MLA if you’re in the humanities, particularly literature or language arts.
- Chicago if you’re in history, some social sciences, or if your publisher or educational institution prefers it. Choose between Notes-Bibliography for traditional humanities writing or Author-Date for social sciences.
- Turabian if you’re a student at an institution that uses Chicago style but you need a more student-focused guide.
If you are in the UK, here are some commonly used style guides:
- Harvard Referencing System – It is used across various disciplines, especially in business, social sciences, and humanities.
- New Oxford Style Manual – This is a comprehensive guide that combines “New Hart’s Rules” (covering grammar and usage) and “The Oxford Dictionary for Writers and Editors.” 1 It’s widely respected and used in publishing, academia, and beyond.
- The Cambridge Handbook for Editors, Authors and Publishers – This handbook is a valuable resource for editors and anyone involved in the publishing process. It provides detailed guidance on copyediting techniques, grammar, style, and preparing manuscripts for publication.
- The Guardian style guide – This guide is specifically tailored to the writing style and standards of The Guardian newspaper. It covers grammar, punctuation, spelling, and preferred word usage, reflecting the newspaper’s distinctive voice
- The Modern Humanities Research Association Style Guide (MHRA Style Guide) – This guide is specifically designed for academic writing in the arts and humanities. It provides guidance on formatting, citation, and referencing, helping students and researchers present their work in a consistent and scholarly manner.
- The Times Style and Usage Guide – Similar to The Guardian’s guide, this one outlines the stylistic conventions of The Times newspaper. It offers guidance on grammar, punctuation, and clarity, aiming to maintain the newspaper’s reputation for quality writing.