Fiber lasers is an area of research investigating laser systems that utilize optical fibers doped with rare-earth elements as the active gain medium. This field encompasses the study of light propagation, amplification, and nonlinear effects within the fiber structure, alongside the design, fabrication, and characterization of fiber-based components and laser architectures. Key characteristics explored include high efficiency, excellent beam quality, power scalability, spectral tunability, and robustness, which are significant for their widespread application across diverse fields such as advanced manufacturing, telecommunications, sensing, medicine, and fundamental scientific research.