What a sidebar is
A sidebar is a self-contained block of text, a graphic or a set of quotes that sits apart from the main narrative of a book. It is usually set off visually, for example in a shaded box, a colored panel or a narrow column in the margin. The material inside can be understood on its own, but it relates to the page or chapter around it.
The word borrows from page layout and journalism. In books, a sidebar is not necessarily at the side of the page, so the name can be a little misleading. A sidebar may run across the bottom of a page or fill a boxed section partway through a chapter.
What sidebars are used for
Authors and editors use sidebars for material that would slow the main text down but is still worth including. Common uses include:
- Background and context, such as a short history of an event or a profile of a person mentioned in the chapter.
- Definitions of specialized terms.
- Case studies, anecdotes and examples that illustrate a point without interrupting the argument.
- Checklists, tips and step-by-step instructions that readers may want to find quickly.
- Timelines, key statistics or summaries that are easier to scan in a box than in a paragraph.
Sidebars also help with pacing. A long run of dense text is tiring, and a boxed item gives the eye somewhere to rest and makes the page easier to skim.
Where you find sidebars
Sidebars are most common in books built for learning or reference:
- Textbooks and study guides, where they often hold definitions, summaries or “did you know” facts.
- Nonfiction and popular science or history titles that use short asides, along with many business books (see our best MBA books).
- Instructional and reference books, including cookbooks, craft guides and manuals.
- Some companion or guide-style books for fiction series, which may include lore, family trees or character notes. These are a good example of how companion books expand a story world.
Novels rarely use sidebars, because a story depends on an unbroken flow. When fiction does include set-apart material, it is usually in a companion volume rather than the novel itself.
Sidebars vs footnotes, boxes and pull quotes
These features are easy to confuse:
- Footnotes and endnotes are short notes tied to a specific spot in the text by a number or symbol. They appear at the bottom of the page or at the end of a chapter or book.
- Pull quotes repeat a line from the main text in larger type for emphasis. They add no new information.
- Sidebars add new material that is separate from the main text and can be read before, after or instead of the surrounding paragraphs.
- Callout boxes is a loose term. Some publishers use it as a synonym for sidebar, others reserve it for short warnings or tips.
Terms vary between publishers, so do not worry if two books use different names for the same thing.
How to read a sidebar
Readers differ on when to read sidebars, and there is no single correct approach. A few options:
- Read the main text first, then return to the sidebars as a second pass.
- Read each sidebar when you reach it, if it clarifies a term you need right then.
- When studying, treat sidebars as optional detail on a first read and as a review tool later.
If you annotate as you read, sidebars are a good place to mark connections to the main text. Our guide to annotation categories for books shows ways to do this.
The main parts of a book
Books are often described as having three broad sections. The exact names and contents vary by publisher and genre, so treat this as a common pattern rather than a strict rule.
Front matter
Front matter comes before the main text. It commonly includes:
- Half title and title page
- Copyright page, which carries publishing details and often a printing number line
- Dedication and epigraph
- Table of contents
- Foreword, preface and acknowledgments
- Introduction, in some books
Body
The body is the main content: chapters, parts or sections. In a novel this is the story itself, sometimes with a prologue and epilogue. In nonfiction it is the chapters, often with sidebars, charts and illustrations.
Back matter
Back matter follows the main text and may include:
- Afterword or epilogue
- Appendices
- Glossary
- Notes and bibliography
- Index
- Author biography
- Colophon, a note about typefaces or production
You will see this section described in different ways. Some sources split books into five parts by counting the cover, front matter, body, back matter and a final element such as the back cover. If someone asks for “the five parts of a book”, it is worth checking which scheme they mean.
The physical parts: what each side of a book is called
- Front cover and back cover are the outer faces.
- Spine is the edge where the pages are bound, usually carrying the title and author.
- Fore-edge is the edge opposite the spine, where you turn pages.
- Head and tail are the top and bottom edges of the book block.
- Recto and verso describe the two sides of a leaf. Recto is the right-hand page, and verso is the left-hand page (the back of the previous leaf).
The materials used for covers and pages also differ by format. A board book and a hardcover have rigid covers, but only the board book has thick paperboard pages throughout.
Other book features worth knowing
Once you know where to look, you can use a book more efficiently:
- The table of contents shows the order of chapters, while the index helps you find specific topics.
- Glossaries explain terms in one place.
- Appendices hold supporting material that does not fit in the main text.
- Annotated editions add commentary alongside the original text.
What is the 50 page rule?
The “50 page rule” is a reading guideline sometimes credited to librarian Nancy Pearl. It suggests giving a book about 50 pages before deciding to stop, with a more generous allowance for younger readers and a shorter one for older readers. It is a rule of thumb about reading habits, not a part of a book, and people apply it in different ways. For other ways to decide whether a book suits you, see the I PICK method for choosing books.
Frequently asked questions
What is the definition of a sidebar?
A sidebar is a set-apart block of supplementary text, graphics or quotes within a book, article or page. It adds context or detail that would interrupt the main narrative.
Are sidebars only in nonfiction?
They are most common in nonfiction, textbooks and reference books. They are uncommon in novels, though some fiction-related guides and companion volumes use them.
Do I have to read the sidebars?
No. They are usually optional, but they often contain definitions, examples or tips that make the main text easier to follow.