The Self-Publisher's 2026 Glossary: Book Production and Printing Terms Explained
Let’s be honest: we could all benefit from adding a few more words to our lexicon, especially when those words have to do with book production and printing terms!
Foglio works with authors at every stage of production and one thing that comes up, reliably, is terminology. As is the case with jargon of various fields, the language of printing and production was developed by industry professionals for industry professionals, and it doesn't naturally explain itself. But knowing the right terms matters more than you might think. When you understand what a preflight check is, or why your printer is asking about colour profiles, you can have more productive conversations, catch problems earlier, and make decisions with real confidence. This glossary covers the book production and printing terms that come up most often in our work with self-publishing authors in Canada, as of 2026.
Print Production Fundamentals
Trim Size
Trim size is the final dimensions of your book after the pages are cut at the bindery. It is the number you will see listed on any print platform: 5.5" x 8.5", 6" x 9", and so on.
This is one of the first decisions you make, and it affects nearly everything that follows: page count, spine width, layout, and cost.
Genre conventions matter here too, as trade fiction typically runs 5.5" x 8.5" or 6" x 9"; children's picture books are often square or landscape-oriented; while a business book may use 6" x 9". Your formatter or typesetter will work within the trim size you choose, so it is worth settling on it before layout begins.
Bleed
When a page is printed and cut, the cutting equipment is precise but not perfect. Small shifts of a millimetre or two are normal. Bleed exists to account for that.
Bleed is the extra strip of design that extends beyond your final page edge. If your cover has a background colour, a photograph, or any graphic that is meant to reach the very edge of the page, that element needs to extend into the bleed area. Without it, even a tiny shift during cutting can leave a thin white border where none was intended.
Safe Zone
The safe zone is the reverse of bleed, and the two concepts work together. Where bleed pushes your design outward, the safe zone pulls your important content inward.
Any text, logo, or element that must not be cut off should sit inside the safe zone, which is typically 0.125" to 0.25" from the trim edge. Think of it as a buffer—your background fills beyond the page edge (bleed), and your critical content stays well away from it (safe zone). Both are invisible guidelines in your design file, but ignoring either one creates visible problems in the finished book.
Gutter
The gutter is the inner margin of each page, the side closest to the spine. When a book is bound, the pages curve slightly toward the centre. If the inner margin is too narrow, text gets pulled into that curve and becomes hard to read.
A well-planned gutter gives readers comfortable access to every word, even on pages deep in the book. For instance, thicker books need more gutter than thinner ones. Your typesetter will account for this but it is worth understanding why that inner margin looks wider than the others when you view your layout file.
Spine Width
The spine is the narrow strip connecting the front and back cover. Its width is not a design choice; it is a calculation based on your page count and the paper your book is printed on.
Most print platforms and printers provide a spine width calculator that enables you to enter your page count and paper type to figure the exact measurement. What matters practically is that your page count should be finalized before your cover designer builds the cover. If the page count changes after the cover is complete, the spine almost certainly needs to be rebuilt!
DPI and Image Resolution
DPI stands for dots per inch. It describes how much detail is packed into a printed image. The more dots per inch, the sharper and more detailed the result. For book printing, 300 DPI is the standard minimum.
A common mistake is judging image quality by how it looks on screen. Screens display at a much lower resolution than print requires, so an image that looks sharp and clear on your computer monitor may still produce a blurry result once printed.
If you are sourcing images from the web, they are almost certainly not print-ready. If you are working with a photographer or illustrator, ask them to supply files at 300 DPI, sized at the dimensions they will appear in the final book.
CMYK and RGB
These are the two main ways colour is created, one for print and one for screens.
Printing uses CMYK: Cyan, Magenta, Yellow, and Black. These four inks are layered in different combinations to produce the full range of colours you see on a printed page.
Screens use RGB: Red, Green, and Blue. Colours on a screen are created by mixing light rather than ink, which allows for a much wider and brighter range than printing can achieve.
The main difference between light and ink, for authors to understand, is that certain colours that look vivid on a screen, particularly bright blues and saturated greens, but will appear noticeably duller when printed. The solution is to work in CMYK from the beginning when preparing print files, rather than converting at the last step. For eBooks and any digital-only images, RGB is the right choice.
Colour Profile
When a file is printed, the printer's equipment needs to know exactly how to interpret the colour values it receives. A colour profile is a small piece of embedded data that provides those instructions to the printer (i.e.: “When you see this value, produce this colour.”)
The most important thing to know as an author is that your print files should have a colour profile embedded before you submit them. A file without one forces the printer's software to guess, and those guesses do not always produce the results you expect. Your designer or typesetter will handle this, but it’s worth knowing what it means when a printer flags a "missing colour profile" in their feedback.
Colour vs. Black and White Interior
One of the most straightforward decisions in book production, and one that surprises a lot of first-time authors with its cost implications, is whether your interior pages are printed in colour or black and white.
For most novels, memoirs, and nonfiction books, black and white interiors are standard. They are significantly less expensive to print per page on both POD platforms and traditional offset presses. Colour interiors are necessary for children's picture books, photography books, cookbooks with food photography, and any book where images are central to the reading experience.
Cover and File Preparation
Preflight
Preflight is the process of checking a print file for technical problems before it goes to the printer. The name comes from aviation, where a preflight inspection happens before the plane leaves the ground. The idea is the same: find the problems before the press runs, because catching them afterward is expensive.
A preflight check looks for things like images that are too low-resolution, fonts that are not embedded in the file, incorrect page dimensions, missing bleed, and colour settings that do not match what the printer expects.
Foglio includes a preflight review as part of our formatting and typesetting process. It is one of those steps that is easy to skip and genuinely painful to wish you hadn't.
Rasterization
Most design files contain two types of elements. The first type is built from clean mathematical shapes and lines, things like text and simple graphics, that can scale to any size without losing quality. The second type is built from a fixed grid of tiny coloured squares, like photographs. When a file is exported for print, some elements from the first type get converted into the second. That conversion is called rasterization.
Where this matters to authors: if your cover includes layered effects or semi-transparent elements, some of those may be converted during export. If the resolution is set too low when that happens, those elements can look slightly soft or degraded in your proof copy.
Print-Ready PDF
A PDF is a common file format that most people have worked with. A print-ready PDF is something more specific: a PDF that has been prepared to meet the exact technical requirements of your printer or platform.
A print-ready file will have the correct page dimensions including bleed, all fonts embedded so they display exactly as intended, the correct colour settings, and all images at sufficient resolution. It is not simply a PDF exported from any program using default settings. Each printing platform publishes its own specifications, and meeting them on the first submission avoids rejection delays and repeated export cycles.
We have covered what print-ready files actually require in detail, and it is worth reading before you export your final files.
Binding, Format, and Paper
Perfect Binding
Perfect binding is the most common binding method for paperback books. The interior pages are gathered into a stack, the spine edges are roughened, and a flexible glued cover is applied. The result is the flat spine you see on most trade paperbacks on a bookshelf.
It works well for books above a certain page count. Below roughly 80 pages, the spine is too thin to hold properly with this method, which is where saddle stitch becomes the better option.
Saddle Stitch
Saddle stitch binding involves folding all the pages in half and stapling through the fold at the spine. It is the binding used for most magazines, brochures, and short guides. For books, it suits shorter works of up to around 80 pages that would not support a perfect-bound spine.
It is durable, cost-effective, and the finished book opens flat, which makes it practical for workbooks, instruction guides, or reference materials that need to lie flat on a desk. It is not appropriate for a novel or memoir.
Case Binding
Case binding is the process used for hardcover books. The interior pages are assembled into a block, and that block is attached to a rigid cover made from boards wrapped in cloth, paper, or a synthetic material. It is the most durable and premium binding option available.
For self-publishers, hardcover is available through both POD platforms and offset printing, though the cost per copy is higher than a paperback. It is worth considering for gift books, commemorative titles, or any project where longevity and a premium feel are part of the reader's experience.
Paper Weight and Stock
Paper weight is a measure of how thick and sturdy a sheet of paper is. In North America it is expressed in pounds (lb), and internationally in grams per square metre (gsm). Common interior paper for trade paperbacks runs from 50 lb to 60 lb. Heavier paper gives a more substantial feel but also increases the spine width and production cost.
Imposition
Imposition is the way pages are arranged on a large sheet of paper before they are printed and cut. Pages are not printed in reading order. They are laid out in a specific pattern so that once the sheet is folded and trimmed, the pages end up in the correct sequence.
For POD printing, this is handled automatically. Where it becomes relevant to authors is in offset printing, where books are printed in large folded sections. Because of how those sections work, page counts often need to fall on specific multiples to avoid waste. Adding or removing a small number of pages can affect your printing cost if it pushes you into or out of one of those sections.
Turnaround Time
Turnaround time is the number of working days between when a print order is placed and when the books are ready to ship. It varies significantly depending on the printing method being used (print-on-demand or offset printing).
Typesetting and Layout
Running Heads
Running heads are the small lines of text that appear at the top of interior pages throughout a book. They typically show the book title on one side and the chapter title or author name on the other. The same information placed at the bottom of a page is called a running foot.
They are a small detail, but they matter to the reading experience. A well-set book feels easy to navigate. Running heads help readers orient themselves, particularly in nonfiction with multiple sections or chapters. Their absence in a trade paperback is the kind of thing readers notice without quite knowing why.
Folio
(Look, Mom! I’m on TV!)
In typesetting, folio simply means page number. The folio is the numeral that appears at the top or bottom of each page. Front matter, meaning the introductory pages at the beginning of the book before the main text starts, is traditionally numbered in Roman numerals (i, ii, iii). The main text begins at page 1 in standard numerals.
Pages that intentionally carry no printed number, such as the title page, blank pages, and full-page images, are called blind folios. The page still counts in the total page count; it simply does not display a number.
Widow and Orphan
A widow is a single short line of text left alone at the top of a new page, separated from the paragraph it belongs to. An orphan is the opening line of a new paragraph sitting alone at the bottom of a page, cut off from the rest of the text that continues on the next page.
Both create a visual awkwardness that tend to interrupt your reader’s flow while reading. Professional typesetting eliminates widows and orphans through careful adjustments to spacing, line breaks, and paragraph fitting.
Digital and eBook Terms
EPUB
EPUB is the standard file format for digital books. It is used by Kobo, Apple Books, Google Play Books, and most reading platforms outside of Amazon. When you publish a digital edition of your book, the file you submit to these platforms is an EPUB.
Unlike a PDF, which locks your content into a fixed visual layout, an EPUB is designed to be flexible. The text flows and adjusts depending on the screen size, the device, and the reader's own settings. This is what allows someone to increase the font size on their phone without the text spilling off the page.
A well-built EPUB handles all of that gracefully; conversely, a poorly built one breaks in ways that are hard to predict without testing across multiple devices. Our eBook design and validation work focuses specifically on producing EPUBs that hold up across all major platforms. Validating your EPUB is essential; learn more about EPUB validation here.
Reflowable vs. Fixed Layout
These are the two structural approaches to eBook design, and choosing between them is a decision made before the file is built.
A reflowable eBook is the flexible kind. Text wraps, resizes, and adjusts to whatever screen is reading it. Most novels, memoirs, and text-heavy nonfiction use this format. It is the most widely compatible option and the one that works best across phones, tablets, and dedicated e-readers.
A fixed layout eBook is the opposite. The page looks exactly as it was designed, regardless of screen size. Nothing reflows or adjusts. This is necessary for children's picture books, illustrated titles, and books where the visual arrangement is inseparable from the content.
The trade-off between the two is that fixed layout files do not scale well on small screens, and readers cannot adjust the font size or style. Switching from one format to the other midway through production typically means rebuilding the file from scratch.
Metadata
Metadata is the collection of information about your book: the title, subtitle, author name, ISBN, description, categories, keywords, publication date, and publisher name. It travels with your book across every platform and database that carries it.
Metadata is how retailers, libraries, and search tools find and categorize your book. Strong metadata is not a marketing task to address after publication. It is a production task, built into your files and your platform listings, and it deserves careful attention at the same stage as your cover and interior layout.
BISAC Codes
BISAC stands for Book Industry Standards and Communications. BISAC codes are a standardized classification system used across the publishing industry to sort books by subject and genre. When you list your book on KDP or IngramSpark, you select BISAC categories that tell retailers, libraries, and distributors exactly what kind of book it is and where it belongs on a shelf or in a search result.
Frequently Asked Questions About Book Production and Printing
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The two terms are related but refer to slightly different things: trim is the finished result, and page size in your software is what you design within.
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No. eBooks are displayed on screens, so images prepared in RGB are correct for digital editions. CMYK is a print standard. If you are producing both a print and a digital edition, your designer will typically prepare separate files optimized for each format. However, image resolution remains just as important.
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Most platforms will reject the file and return a report explaining what failed. You address each item, export a corrected file, and resubmit. Building a preflight check into your workflow before your first submission is the more efficient path.
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No. You provide your final page count and paper stock to your cover designer, and they calculate the spine width using your printer's specifications. Most POD platforms also offer cover template generators that do this automatically.
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It means your PDF meets the platform's technical requirements: correct page dimensions with bleed, embedded fonts, the right colour settings, and images at sufficient resolution.
Book Production and Print Made Simple
No gatekeeping here! Understanding these common book production terms will empower you on your self-publishing journey. Having a command over the vocabulary, will ensure that your conversations with printers, designers, and formatters become much more productive. You’ll spend less time decoding feedback and more time making good, informed decisions about your book.
