Royalty Calculation is a crucial concept in the publishing industry, especially for children's books. It involves the process of determining how much an author earns based on the book's sales, typically expressed as a percentage of the book's retail price or net sales. Different publishers may have varying royalty structures, which can include advances against royalties, tiered percentages, and supplementary income from foreign rights or adaptations. Understanding this calculation helps authors predict their earnings and make informed decisions about their publishing contracts.