DITA uses a topic-based approach to authoring. A topic in DITA is the most granular entity of information. According to the DITA specifications, a topic should be short enough to be easily readable, but long enough to make sense on its own.
To cover separate content such as concepts, tasks, reference, the DITA standard specifies different information types. Each information type defines structured elements that aid in authoring the relevant content. For example, the task type defines elements such as context, example, steps, and result.