The Combined DNA Index System, or CODIS, is a national database used in the United States to store and compare DNA profiles from crime scenes, convicted offenders, and missing persons. It helps law enforcement agencies identify suspects and solve cases by matching DNA evidence collected during investigations. CODIS operates at local, state, and national levels, allowing for collaboration among various law enforcement agencies. The system contains DNA profiles that are anonymized to protect individuals' privacy while still providing valuable information for criminal investigations. This technology has significantly improved the ability to solve crimes and exonerate innocent individuals.