Mapplet input. You can pass data into a mapplet from data sources or Input transformations or both. If you validate the mapplet as a rule, you must pass data into the mapplet through an Input transformation. When you use an Input transformation, you connect it to a source or upstream transformation in the mapping.

Mapplet output. You can pass data out of a mapplet from data sources or Output transformations or both. If you validate the mapplet as a rule, you must pass data from the mapplet through an Output transformation. When you use an Output transformation, you connect it to a target or downstream transformation in the mapping.

Mapplet ports. You can see mapplet ports in the mapping editor. Mapplet input ports and output ports originate from Input transformations and Output transformations. They do not originate from data sources.