This guide discusses four significant trends in simulation technologies within the context of lean manufacturing. It outlines how simulation software can assist manufacturers in optimizing machining, cutting, and design processes. Despite a high awareness of simulation tools, only a fraction of manufacturers actively utilize them, primarily due to cost and accessibility issues. The document details the growth of simulation technologies in areas such as DIY, additive manufacturing, factory floor planning, and fluid structure analysis. It emphasizes the importance of continuous improvement, a core principle of lean manufacturing, and highlights how simulation can enhance production efficiency and accuracy. Additionally, it presents the trend of cloud-based simulation software, which aims to make these tools more accessible to companies of all sizes. The guide also covers the integration of additive and subtractive manufacturing processes in simulation, the need for rapid factory room design, and the role of fluid structure analysis in extending tool life. The future of simulation technologies is anticipated to evolve, focusing on tailored solutions for manufacturers.