Software renovation is using tomorrow's technology to bring yesterday's software to the level of today. In this paper, we provide an overview of this research area. We start (in this section) by exploring the need for software renovation. Moreover, we provide definitions of the basic terminology, and pointers to the most important literature. We then proceed to discuss two aspects of software renovation in more detail. In Section 2 we study how we can increase our understanding of a given legacy system, and how we can apply this knowledge for the purpose of migrating the legacy to object technology. Techniques like type inference and concept analysis play an essential role here. In Section 3 we deal with ways of building renovation factories that are capable of restructuring legacy systems of millions of lines of code in an entirely automatic manner. In Section 4 we conclude this tutorial and present some findings based on our experience in software renovation research.
Initially triggered by concerns regarding the renovation of our own software, we have since 1996 closely cooperated with several Dutch banks, and (inter)national software houses and telecommunications firms on the question how to prepare their software system assets for future flexibility. The work presented here is directly driven by their industrial needs.