User-data allows scripts to run on instance bootup, enabling automated configuration. IndexMedia improved deployment time from 30 minutes to 90 seconds by splitting scripts into static and instance-specific parts. AutoScale automatically launches and terminates instances to maintain performance within specified bounds based on metrics like CPU utilization. With just four commands, IndexMedia set up an AutoScale group with a scaling policy and alarm to dynamically scale their fleet based on load, solving their problem of maintaining consistent user experience.