Does anyone know what supplementary picture books mean? In ancient books

Supplementary picture book, that is to say, this book originally had no pictures, and later someone made pictures for this book, so the later book was called supplementary picture book.

For example, the earliest version of Biography of Women had no pictures. Later, in order to facilitate the spread, or for better sales, the bookstore provided pictures for each character, so the later version was called Biography of Women.