The death knells of the mainframe have been sounded for years now, yet despite all these calls, the mainframe lives on. It has not died, and it is showing no signs of dying. Despite competition for workloads from high-end Unix and Intel-based servers, as well as the rise of cloud computing, mainframes – or ‘big iron’ as they’re colloquially referred to – persist. However, the terminals or ‘green screens’ that were traditionally used to communicate with mainframes have not persisted, instead being replaced with terminal emulation software ( 3270 emulation, for example), which mimics the role terminal hardware once played.