Hydrogen fusion is a nuclear reaction where two hydrogen nuclei combine to form a helium nucleus, releasing a significant amount of energy in the process. This reaction occurs naturally in stars, including our Sun, where immense pressure and temperature allow hydrogen atoms to overcome their repulsion and fuse together. In controlled environments, such as in fusion reactors, scientists aim to replicate this process to generate clean and sustainable energy. The challenge lies in achieving the necessary conditions for fusion to occur while maintaining stability and efficiency, making it a key area of research in the quest for alternative energy sources.