This chapter discusses cyber ranges, which are dedicated network environments used for cybersecurity training purposes. We first provide an overview of this type of training platforms, emphasizing the significance of their use during training, as well as the two main categories of cyber ranges. The first category, general cyber ranges, refers to those training platforms employed for generic cybersecurity training. For this category, we provide several examples classified based on the organizations that operate them, namely government, private sector, or academic institutions. The second category, specialized cyber ranges, includes those training platforms that are dedicated to specific application areas. The examples we provide for this category relate to the domains of IoT, ICS/SCADA, critical infrastructure, as well as healthcare. For each of the two categories of cyber ranges, we conduct a comparative analysis of the main characteristics of those cyber ranges and discuss several issues that are particular to each category.