Luhmann's theory combines different layers of conceptualisation, which are used to analyse different and interlaced objects. These layers include the general concept of system, the more specific concept of social systems, the concepts of society, interaction and organisation as particular types of social system. Thus, Luhmann's theory provides a very complex and rich background to describe and explain all the most important aspects of education, i.e. the function and structures of education and the ways in which it is included in society, the historical background of education, the importance and structures of classroom interaction, the meaning of teaching and school organisation, the pedagogical reflection on education. Finally, Luhmann's theory allows both differentiation and connection between pedagogical reflection and sociological analysis.