Repair techniques is a systematic study of methodologies and processes developed to restore the integrity, functionality, and durability of entities that have sustained damage. This academic concept investigates the mechanisms of damage, the application of appropriate interventions (ranging from microscopic material processes to macroscopic structural or biological repairs), and the evaluation of repair outcomes across diverse domains such as materials science, civil engineering, and biomedical engineering. Its significance lies in extending service life, enhancing resilience, and promoting sustainability by mitigating the effects of degradation and failure.