The administration interface makes it possible to swap (replace) a certain node (page) with another one. Please note that this feature is considered to be advanced functionality. It is typically useful when you wish to change the type of a node but keep the structure which is below it. For example, there might be a situation where you wish to replace a folder that contains several news articles (or even a complex hierarchy) with a different type of node (for example a special kind of folder).
This feature is also useful when there is a need to change one of the top level nodes (Content, Media, User). In eZ Publish, a top level node can not be removed from the system, but it may be swapped/replaced with another node. For example, if you want to use a news article instead of a folder (which is the default) as the top level node, you could simply swap the folder with an existing article node.
The following text explains how you can swap a node with another one.