Lecture 10 and the XML content are not relevant for the exam. This class is an introduction to the theory of tree automata and their applications. Properties of recognizable tree languages as well as their relation to natural language parsing and XML processing will be studied. The lecture (Vorlesung) will be supplemented by a tutorial (Übung) where the contents of the lecture will be recapitulated with weekly assignments and programming exercises. The theory of tree automata and tree grammars has been studied since the 1960s. Tree automata and tree transducers have proved a useful tool in compiler construction, XML processing, verification and not least natural language processing.