What is Data Template and Layout Template?

Data Template:
Datatemplate is an xml structure which contains the queries to be run against the database so that desired output in xml format is generated, this generated xml output is then applied on to the layout template for the final output

Layout Template:
Layout template defines how the user views the output, basically it can be developed using Microsoft word document in rft (rich text format) or Adobe pdf format. The data output in xml format (from Data template) will be loaded in layout template at run time and the required final output file is generated.