Digital twin technology creates a digital replica of a physical object or system that can be used to gather data, understand past and current behavior, and predict future performance. The digital twin is made possible by sensors that collect data from physical assets and IoT technology. The document discusses the history and development of digital twin technology, how it is used across various industries like manufacturing, healthcare, and aerospace to optimize operations and reduce costs, and the future potential of digital twins including using them to make decisions and interact after death.