This article reviews the development of functional microfluidics, covering its theoretical foundations, microfabrication methods, and diverse applications. It highlights the progress in materials science, microfabrication, and the use of microfluidic devices in various fields such as heat sinks, clean water production, chemical reactions, sensors, biomedicine, and microrobotics. The review discusses the theories behind microfluidic phenomena, including capillary forces, wettability, and hydrodynamics, as well as the simulation methods used to study these phenomena. It also explores the materials and fabrication techniques used to create functional microfluidic devices, including laser methods, molding, imprinting, lithography, and 3D printing. The article emphasizes the importance of these technologies in achieving carbon neutrality and calls for interdisciplinary collaboration to advance the field. Key challenges and future directions for functional microfluidics are also discussed, focusing on materials, scalability, and programmability. The review aims to inspire researchers from various disciplines to collaborate and drive innovation in the development and application of functional microfluidic devices.This article reviews the development of functional microfluidics, covering its theoretical foundations, microfabrication methods, and diverse applications. It highlights the progress in materials science, microfabrication, and the use of microfluidic devices in various fields such as heat sinks, clean water production, chemical reactions, sensors, biomedicine, and microrobotics. The review discusses the theories behind microfluidic phenomena, including capillary forces, wettability, and hydrodynamics, as well as the simulation methods used to study these phenomena. It also explores the materials and fabrication techniques used to create functional microfluidic devices, including laser methods, molding, imprinting, lithography, and 3D printing. The article emphasizes the importance of these technologies in achieving carbon neutrality and calls for interdisciplinary collaboration to advance the field. Key challenges and future directions for functional microfluidics are also discussed, focusing on materials, scalability, and programmability. The review aims to inspire researchers from various disciplines to collaborate and drive innovation in the development and application of functional microfluidic devices.