BluePrinting
BluePrinting is the framework that enables SDL Web users to share content across Web sites, and to create local copies (for example, translations) of content.
The concept of BluePrinting is a way in which users of the SDL Web Content Manager can organize content. In BluePrinting, Publications in the Content Manager (which typically correspond to Web sites) are organized in a hierarchical structure. Publications have a parent-child relationship with other Publications: each Publication can have a parent Publication, a child Publication, or both. The BluePrint Hierarchy button in the Manage tab of the ribbon toolbar shows this relationship between Publications.
Shared items
If a Publication B is a child Publication of another Publication A, then all content items created in A are also available in B and in all of B's child Publications: those content items are known as shared items. You can only edit these items in Publication A, but you can localize them in B or in any of B's children.
Localizing
If a (properly authorized) user localizes an item in B that is shared from A, that user creates a local copy of the item. This local copy is initially identical to its parent item, but it is editable in B. Any changes made to the item will be available only in B and in B's child Publications. A good example of why a user would want to localize content is to translate it from the language of the parent Publication into the language of the child Publication (e.g. Publication A is an English-language site, and Publication B is the French-language equivalent).
Unlocalizing
Once localized, a local copy is independent of its parent item: any changes made to the parent item are no longer shared down to the local copy, and any changes made to the local copy have no effect on the parent item. It is possible, however, to unlocalize the item. If you unlocalize an item, you destroy the local copy you made (and any changes you made since you localized it) and return to the original situation: you share the item from the parent Publication.
Local items
You can also create local items in B, which are editable in B and are only available in B and in B's child Publications.
Custom BluePrint structure
Each implementation of SDL Web is different and has its own hierarchy (or hierarchies) of BluePrint structures. How you work with BluePrinting very much depends on the specific BluePrint structure implemented in your organization. Consult the person responsible for managing SDL Web software in your organization to find out more about your organization's BluePrint hierarchy.