# Map-based linking (`maplink`)

This step collects links based on a map and moves those links into the referenced topics. The links are created based on hierarchy in the DITA map, the `@collection-type` attribute, and relationship tables. This step is implemented in XSLT and Java.

The `maplink` module runs an XSLT stylesheet that evaluates the map; it places all the generated links into a single file in memory. The module then runs a Java program that pushes the generated links into the applicable topics.