|DITA map files / Purpose of ditamap files|
A publication (also known as the output or the deliverable) is the document, Web site, eBook, Help system or other product produced when a collection of DITA topics is processed through a publishing program.
In the DITA sense, a publication is the name given to a set of topics that are assembled (from a pool of DITA source files) to form a deliverable document. Because the term publication evokes a mental image of a printed work, the terms output or deliverable are sometimes used for differentiation.
When produced as a printed document, we might call the output of the DITA publishing process a "book". When produced for online delivery, we might call the output a "Web site". When produced as a CHM file, we might call the output a "Help system".
The term collection is used to describe a potential publication in the DITA source. A ditamap collection is processed to become a publication. In other words, collection describes the source content, while publication describes the output format. A collection is defined in DITA through a ditamap, or multiple embedded ditamaps.
The process of transforming DITA source into an output format is known as publishing, processing, or transformation, and the software tools for the process are known as processors, transformers, or publishing engines.