A mapplet is a reusable object that you create in the Mapplet Designer. It contains a set of transformations and lets you reuse the transformation logic in multiple mappings.
For example, if you have several fact tables that require a series of dimension keys, you can create a mapplet containing a series of Lookup transformations to find each dimension key. You can then use the mapplet in each fact table mapping, rather than recreate the same lookup logic in each mapping.
When you use a mapplet in a mapping, you use an instance of the mapplet. Like a reusable transformation, any change made to the mapplet is inherited by all instances of the mapplet.
Mapplets help simplify mappings in the following ways: