[en] This chapter defines and presents the kinds of software ecosystems that are targeted in this book. The focus is on the development, tooling and analytics aspects of “software ecosystems”, i.e., communities of software developers and the interconnected software components (e.g., projects, libraries, packages, repositories, plug-ins, apps) they are developing and maintaining. The technical and social dependencies between these developers and software components form a socio-technical dependency network, and the dynamics of this network change over time. We classify and provide several examples of such ecosystems, many of which will be explored in further detail in the subsequent chapters of the book. The chapter also introduces and clarifies the relevant terms needed to understand and analyse these ecosystems, as well as the techniques and research methods that can be used to analyse different aspects of these ecosystems.
