Review the following terms in order that you can fully understand the information provided in this chapter.
Version
One variation of a publication that has some content in common with another variation of the same publication and some content that is unique.
For example, a publication that has common images, but one variation has English text and the other has Spanish text, can be said to have an English version and a Spanish version.
Base content
Content that is the same in (common to) all versions.
For example, if two versions of a publication have the same images, the base content is the common images.
In a job with editions, each edition can have a different set of base content.
Change content
Content that is unique to a version.
For example, if a publication has common images, but one variation has English text and the other has Spanish text, the change content is the English text and the Spanish text.
In a job with editions, change content is content that is unique to a version, or an edition, or both.
Layer
A single thickness of a page that contains page content. Each layer of a page has the same page specifications as other layers of that page, but different content. A page usually consists of two or more layers.
Base layer
A layer that contains base content.
Change layer
A layer that contains change content.
Figure 1. Versions and layers
Versioned page
A collection of refined pages that make up all versions of a single page, including the required layers for each version.
Edition
An edition is a set of versions, which has different base content from another set of versions of the same publication. Essentially, editions occur when you have versions within a version. Each edition includes multiple versions. 
Figure 2. Editions with versions—the English and Spanish editions each have two versions for East and West pricing