Home Glossary

Reference · Updated 2026

eBook Publishing & Marketing Glossary

Clear, current definitions for the terms indie authors, coaches, and creators actually need to know. Each entry is concise enough for quick reference and thorough enough to settle a disagreement.

Author Brand

Pen Name

A fictional author name used on a book cover instead of the author's legal name. It's legal everywhere and common in self-publishing, especially for authors writing across multiple genres or running multiple brand identities. Royalties still flow to the legal person; the pen name is just a marketing surface.

KDP & Amazon

Amazon A+ Content

Replaces the plain-text book description on your KDP product page with rich image and text modules. Amazon data shows products using A+ Content see roughly 5.6% higher conversion on average; for books the lift is typically 8-15%. Basic A+ is free for all KDP authors.

ASIN

A 10-character code Amazon assigns to every product, including every Kindle ebook. It's Amazon-only and works as the product's unique identifier — unlike an ISBN, you can't buy or use an ASIN outside Amazon.

KDP Select

Amazon's optional enrollment program that grants access to Kindle Unlimited page-read revenue, Kindle Countdown Deals, and Free Book Promotions, in exchange for 90-day Amazon exclusivity on the digital edition.

KENP

Kindle Edition Normalized Pages — Amazon's standardized page-count measurement for Kindle Unlimited. It normalizes every eBook to a common font, spacing, and margin model, typically 1.0-1.3x your manuscript's page count.

Kindle Countdown Deal

A 7-day promotional pricing feature for books enrolled in KDP Select. Authors can temporarily drop price while keeping the 70% royalty rate. Available in the US and UK only, one per 90-day Select period per book.

Kindle Unlimited

Amazon's subscription eBook service. Authors enrolled in KDP Select earn per-page-read revenue from the KDP Select Global Fund, typically $0.004-$0.005 per normalized page.

Marketing & Ads

ACoS

Advertising Cost of Sale — the percentage of ad-attributed sale revenue spent on advertising: (ad spend ÷ ad revenue) x 100. Most indie authors target ACoS under 40% for non-fiction, under 60% for fiction in Kindle Unlimited.

Lead Magnet

A free piece of content — typically an 8-15 page eBook, cheat sheet, template, or video — offered in exchange for a prospect's email address, turning anonymous visitors into subscribers who can be nurtured into buyers.

Tripwire Offer

A low-priced product ($5-$25) offered right after a prospect opts in to a lead magnet. Its purpose isn't primarily revenue — it converts a freebie-seeker into a first-time buyer, since paying customers are 4-10x more likely to buy again.

Publishing

Book Blurb

The short marketing description (typically 120-250 words) on a book's back cover, Amazon listing, and sales pages. Its job isn't to summarize the plot — it's to convert a browser into a buyer in 30-60 seconds.

Publishing & Distribution

BISAC Codes

Standardized category codes that classify books by subject. Each code has a letter prefix (like FIC for fiction) and six digits identifying the subcategory — choosing the right ones determines which Amazon categories your book can rank in.

Book Metadata

The structured information that describes your book to retailers — title, subtitle, description, keywords, categories, ISBN, price, series info. Good metadata drives discoverability; bad metadata is why most self-published books never get seen.

ISBN

A unique 13-digit identifier assigned to every edition and format of a published book. Optional for ebook-only Amazon KDP; essential for wide distribution, print, or libraries.

Print on Demand (POD)

A publishing model where physical books are printed one at a time after an order is placed — no inventory, no bulk printing. Lower margin per unit, but zero inventory risk makes it the default for most indie authors.

Publishing Economics

Author Royalty

The payment an author receives per sale or per page read. Self-publishers on Amazon KDP earn 35% or 70% of list price depending on tier; traditional publishers typically pay 7.5-15% on print and 25% of net on ebooks.

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