Final answer:
The question about three main types of XML documents may refer to specific contexts, but generally, XML documents are categorized by function, such as data storage documents, documents for transformation into other types using stylesheets, and SOAP-based documents for web services.
Step-by-step explanation:
A student inquired about the three main types of XML documents to remember. While the question references 'Documentation III: Analysed Markings and Diary Perspective Schema,' by Kelly, this appears to be a specific contextual example rather than a general classification of XML documents. Typically, XML documents do not have a strict typology, but they can generally be characterized by their function or schema. In a broader sense, XML documents may be categorized based on their usage, such as:
- Simple data storage documents, which store data in a structured format.
- Documents that are designed to be transformed into other types of documents or reports through the use of stylesheets, such as XSLT.
- SOAP-based documents used in web services for messaging and communication between systems.
Without more context, we cannot definitively categorize the XML documents mentioned in 'Documentation III.' Therefore, the answer above provides a generic classification that may be helpful in understanding different uses of XML documents.