The book industry, like any other, is rife with jargon and esoteric terminology. Here's a brief rundown of some of the key terms you might encounter.
Trim size
Selecting a trim size is the first step in book design. Different sizes (5.5 x 8.5 or 6×9) are used for different types of book. If your book is more than 250 pages, a small trim size (5 x 8 or smaller) will create a thicker book and can potentially turn off book buyers. Designers also work with authors to choose format: hardback with or without jacket, paperback, casebound, ebook.
Margins
Margins are perhaps the most important part of a book layout after trim size. A book page has three margins (outside, top, bottom) and a gutter (the inside margin where the pages are glued or sewed together). Each of those margins has a particular job:
The outside margin, often called the thumb margin, is where the reader holds the book.
The top margin is where the author, name of the book, and sometimes the page number is found.
The bottom margin provides white space below your text block.
The gutter makes sure the text doesn’t slip into the center binding area.
In classic book design, the outside, top, and bottom margins are close in size (often around half an inch each). The gutter is the largest (usually .75 – .9 inches), to accommodate binding.
Typography
The next thing a book designer determines is typeface. Books are traditionally set in readable, serif fonts like Garamond, Caslon, Baskerville and Goudy. Guidebooks, art books, cookbooks, and other genres often use sans-serif for their modern feel if the book isn't too text-heavy. The font must be legible and well-suited for the book’s content and genre. Some books, like mysteries, are often set larger because their audience tends to be older. Guidebooks are often set in a grid, or 2-column layout to pack in more text.
Equally important is the white space between the lines, known as “leading.” Leading allows your readers to read your book without getting a headache. It prevents your readers from becoming lost in paragraphs. Leading works in tandem with the text block (text width and line number) and the font type. Generally, 33-35 lines per page is standard.
Running Heads and Folios
Running heads are the headings at the top of the page that provide the author, book name, and page name/number. They should be small enough to not intrude on the text, while still legible and clear. Sometimes the page number, or “folio,” will be at the bottom or even side of the page. Running heads and folios (rh/f) provide a visual frame for your text block as well as a way for readers to navigate through the pages. Enough space must exist between the rh/f to differentiate it from the text block.
Images
If your book has photographs, maps, illustrations, or line art, the layout must accommodate them. Depending on the genre, the text and art will interact in different ways. A children’s book has different needs than a cookbook. An art or photography book often has large photos on each page, with simple captions under the photos and a brief introduction by the artist at the beginning.
Design Details
Good designers use unique, often quirky, little details to make a design stand out. Sometimes less is more, but sometimes enhancing with details can add to a reader’s enjoyment. For example, a cute graphic, or “dingbat,” can be added to clearly define sections. Other details--such as boxes, clip art, and type features--can highlight important concepts or set off important information.
Resources
Here are just a few resources to help you navigate the detail-heavy and traditional world of book making.
Fiona Raven and Glenna Collett, 2017.
Book Typography: A Designer’s Manual Mitchell & Wightman, 2005.
Thinking with Type, 2nd Ed. Ellen Lupton, 2010.
Robert Bringhurst, 2013