Very often I come across the question – Why DITA? Here is an interesting analogy to try and answer the same. The purpose is not to define DITA, but to share my perspective on what DITA may imply for the technical authoring community.
In the XML authoring paradigm, the document is split into structure, content and style, which are analogues to Driving Rules (structure), car (content) and road network (style). If the content and the style are as per same structure (DTD/Schema), you can generate the output by combining content with the style-sheet. However, it would not be possible to generate proper output using content and style sheets based on different structures. Similarly, if the cars and the road networks are designed as per same driving rules everything runs smoothly. However, if they are designed as per different driving rules, there would be chaos. E.g. it is difficult to drive a car designed for the US (right hand drive) in UK, where the road networks are designed as per left hand drive.
In a hypothetical world, where each country has its unique set of driving rules, the design of cars and road networks are unique to each country. It is difficult to drive a car designed for country X in country Y. XML authoring leads to a similar situation. Each organization and team has its own set of driving rules (Structure – DTD/Schema), hence it is difficult to share content or apply the same style sheet to content aggregated from different sources.
Imagine if all countries followed the same driving rules. All cars can be driven in any country, and the road networks could be designed, as per the driving rules, without any knowledge of the actual cars that would drive on it. DITA is similar to these universal driving rules. If everyone follows the DITA specifications, it would be easy to share content and apply the same style sheets to the aggregated content.
There have been other standards (universal driving rules) that have come up in the past. But they were good for specific kind of documents (terrains). DITA is different, as it is based on the premises that the same set of driving rules cannot be applied to all terrains (desert, mountains, city, etc.). Therefore, DITA allows each country to specialize the driving rules for its own unique requirements. In addition, DITA also has recommendations on the content (car) design – i.e. topics. This further makes it easier to reuse, manage and share content.
This is what makes DITA promising and makes it worth a serious consideration.