I am not sure if html belongs to structured, semi-structured or unstructured data. I hope you can answer me this question.
3 Answers
HTML is a hierachical tree data structure. For example, XML and XLST are both hierarchical tree data structures that produce a structured hierarchical tree data structure. See Microsoft XSLT and XSLT Programmers Reference from Wrox. Therefore, from a definitional point of view HTML is a data structure.