transclusion

From Wikipedia:

In computer science, transclusion is the inclusion of part of a document into another document by reference.

For example, an article about a country might include a chart or a paragraph describing that country's agricultural exports from a different article about agriculture. Rather than copying the included data and storing it in two places, a transclusion embodies modular design, by allowing it to be stored only once (and perhaps corrected and updated if the link type supported that) and viewed in different contexts. The reference also serves to link both articles.

The term was coined by hypertext pioneer Ted Nelson in 1982.

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