Steam Methane Reforming (SMR) is the most widely used method for producing hydrogen, primarily from natural gas. It involves reacting methane with high-temperature steam to produce synthesis gas (syngas), a mixture of hydrogen and carbon monoxide. This syngas undergoes a second step—the water-gas shift reaction—where carbon monoxide reacts with steam to yield more hydrogen and carbon dioxide. Hydrogen is then purified for industrial use, while the CO₂ may either be released or captured, depending on the process. Grey hydrogen refers to hydrogen produced via SMR without capturing the resulting CO₂ emissions, contributing significantly to greenhouse gases. In contrast, blue hydrogen includes carbon capture, utilization, and storage (CCUS) technologies to trap and store CO₂, reducing environmental impact. The effectiveness of blue hydrogen depends on the efficiency of carbon capture and the availability of secure storage solutions. Countries like the United States, Canada, United Kingdom, Norway, Japan, and South Korea are leading in SMR and blue hydrogen development. These nations leverage natural gas resources, industrial infrastructure, and carbon storage capabilities to scale hydrogen production while minimizing emissions. Syngas, the intermediate product of SMR, is key to hydrogen production. It is converted into hydrogen through the water-gas shift reaction, which boosts hydrogen yield and facilitates CO₂ separation. Hydrogen is then purified using methods such as pressure swing adsorption or membrane separation. While green hydrogen—produced from water electrolysis using renewable energy—is ideal, it remains costly and less scalable. Blue hydrogen offers a practical transition solution by using existing infrastructure with reduced carbon output. Government incentives, policy support, and technological advances in SMR and CCUS are helping make blue hydrogen a central component of global decarbonization strategies and a vital step toward a low-carbon energy future.