Can topics be nested?

Topics can be nested to create larger document structures. However, the nesting always occurs outside the content boundary, so that child and parent topics can be easily separated and reused in different contexts. Here is a sample nesting structure: <topic>
<title>A general topic</title>
<shortdesc>This general topic is pretty general.</shortdesc>
<body><p>General topics are not very specific. They are useful for
the big picture, but they don't get into details in the same way as
more specific topics.</p></body>
<topic>
<title>A specific topic</title>
<shortdesc>This is a more specific topic.</shortdesc>
<body><p>Specifically, this is more specific.</p></body>
</topic>
</topic>

You can author topics either as nested structures or as individual stand-alone documents. In the latter case, you assemble the documents into nested structures as required, such as when delivering printed or printable information that has a part and chapter hierarchy.

The nested structure gives a sequence and hierarchy of topics within a topic collection. In a Web environment you could disassemble this structure into individual topics and preserve the hierarchy in a generated navigation map or table of contents. However, if the Web is the main delivery vehicle, you might want to author the topics as separate documents and then apply several tables of contents to the same collection of topics.

This article shows you how to create multiple topics inside a single topic, but how to you reference them in a map, so your map has all the topics listed? 

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