This book is divided into three parts. The first part discusses the Metaverses basics, development, and optional applications such as 3D virtual dressing room-based user-friendly Metaverse, the use of Metaverse in the healthcare and environment sectors as well as the ethics of the Metaverse and digital virtual environments. Part two presents some chapters that discuss emerging technologies in the Metaverse world including IoT, digital twining, and artificial intelligence and shows its impact on climate change. The third part contains chapters discussing cybersecurity in the Metaverse including blockchain technology opportunities and applications and the threat of the digital humanities in the Metaverse. The book is suitable for students and academics aiming to build up their background on the Future of the Metaverse in the Virtual Era and Physical World.