In this chapter, we introduce and outline four different 21st century technologies. The most important 21st century technology is ICT–information and communication technology. In many ways, it has come to be the backbone of society, and provides the infrastructure upon which other technologies can sit. It is extremely pervasive, rapidly increasing, and undoubtedly important. The future of ICT will see ever-increasing speed, reliability, interconnectivity and sophistication approaching that of the capabilities cyberspace offer.