The Indian Ocean tsunami warning system works as follows: 1) Earthquakes in the Indian Ocean are detected by various data sources which transmit this data to warning centers in Hawaii and Japan to analyze and determine potential for tsunamis. 2) These warning centers predict tsunami arrival times and share this information with regional agencies. 3) These regional agencies then alert local populations through methods like radio, TV, SMS, and loudspeakers. Drills help facilitate quick evacuations.