In recent years, Unity and Unreal have made inroads into non-gaming categories, including engineering, filmmaking, and computer-aided design. In 2019, as discussed earlier, the Hong Kong International Airport used Unity to build a “digital twin” that could be connected to myriad sensors and cameras throughout the airport to track and evaluate passenger flows, maintenance, and more—all in real time. The use of “game engines” to power such simulations does make it easier to produce a Metaverse which spans both the physical and virtual planes of existence.