The Metaverse offers a second world beyond reality, where boundaries are non-existent, and possibilities are endless through engagement and immersive experiences using the virtual reality (VR) technology. Many disciplines can benefit from the advancement of the Metaverse when accurately developed, including the fields of technology, gaming, education, art, and culture. Nevertheless, developing the Metaverse environment to its full potential is an ambiguous task that needs proper guidance and directions. Existing surveys on the Metaverse focus only on a specific aspect and discipline of the Metaverse and lack a holistic view of the entire process. To this end, a more holistic, multi-disciplinary, in-depth, and academic and industry-oriented review is required to provide a thorough study of the Metaverse development pipeline. To address these issues, we present in this survey a novel multi-layered pipeline ecosystem composed of (1) the Metaverse computing, networking, communications and hardware infrastructure, (2) environment digitization, and (3) user interactions. For every layer, we discuss the components that detail the steps of its development. Also, for each of these components, we examine the impact of a set of enabling technologies and empowering domains (e.g., Artificial Intelligence, Security & Privacy, Blockchain, Business, Ethics, and Social) on its advancement. In addition, we explain the importance of these technologies to support decentralization, interoperability, user experiences, interactions, and monetization. Our presented study highlights the existing challenges for each component, followed by research directions and potential solutions. To the best of our knowledge, this survey is the most comprehensive and allows users, scholars, and entrepreneurs to get an in-depth understanding of the Metaverse ecosystem to find their opportunities and potentials for contribution.

翻译：元宇宙通过虚拟现实（VR）技术提供了超越现实的第二世界，在这里界限不复存在，通过沉浸式体验与互动，可能性无穷无尽。若得到精准开发，元宇宙的进步可使技术、游戏、教育、艺术、文化等多个学科受益。然而，充分挖掘元宇宙环境的潜力是一项需要正确指导与方向的模糊任务。现有关于元宇宙的综述仅聚焦于其特定方面和学科，缺乏对整个过程的全局视角。为此，需要更具整体性、多学科、深入且兼顾学术与工业视角的评述，以全面研究元宇宙开发管道。针对这些问题，本综述提出了一种新颖的多层管道生态系统，其组成包括：（1）元宇宙计算、网络、通信及硬件基础设施，（2）环境数字化，以及（3）用户交互。针对每一层，我们讨论了详述其开发步骤的组件。同时对于每个组件，我们考察了一组使能技术与赋能领域（例如人工智能、安全与隐私、区块链、商业、伦理与社会）对其发展的影响。此外，我们阐释了这些技术在支持去中心化、互操作性、用户体验、交互与货币化方面的重要性。本研究突显了每个组件面临的现有挑战，随后给出了研究方向与潜在解决方案。据我们所知，本综述最为全面，能使用户、学者与创业者深入理解元宇宙生态系统，以发现其贡献机遇与潜力。