Comparison of Table Type Taxonomies

Tables are widely used to present related data in various formats and media. In particular, an immense number of HTML tables can be found on web pages. These tables serve as a valuable source of data for applications such as web mining, question-answering systems, and knowledge base development. However, not all HTML tables contain actual relational data. Many of them are used primarily for layout and navigation purposes. On the other hand, genuine tables may have different layouts, formatting, and content. One of the challenges in extracting data from web tables is to identify the main functional and layout types and properties of the tables that are commonly found on the internet. Currently, we have a wide range of taxonomies that classify table types and their properties. These taxonomies can be used to categorize tables and select the appropriate method for processing tabular data based on their specific type. Although the existing taxonomies provide a variety of table types, they often use confusing terminology. This paper aims to provide an overview of these taxonomies by aligning their terminology and comparing them in a qualitative manner.