Trees and XML
From Ian Stark
From the strict rectangles of structured data to the more generous triangles of semistructured data. This lecture gives an overview of what kind of data is seen as “semistructured”; the idea of trees as a mathematical model of data; the particular form of trees in the XPath data model; and their textual representation in XML — the Extensible Markup Language. Also, possible communication from an alien intelligence.
Link: Web page for this lecture