What is the difference between the bound History books and the loose-leaf package version?

There are three bound History books - Musical Overview, Early Music, and Modern Music - and three loose-leaf packages with the same name. Each bound book has an ISBN, Table of Contents, index, and page numbers. The loose-leaf packages have different colored paper, depending on the era:

Middle Ages: cream
Renaissance: blue
Baroque: grey
Classical: ivory
Romantic: green
20th century: white

Longer sections also have 'page 1 of 9', etc. at the bottom of each page to make organization easier. Loose-leaf packages often have choices for topics that you can add, and the pages are three-hole punched, ready to fit into a standard binder.