World Data API consolidates the reference data that developers typically pull from multiple separate APIs. Instead of integrating REST Countries for geography, TimezoneDB for timezones, Calendarific for holidays, and separate sources for airports and astronomy - you get one API with one authentication scheme, one response format, and interconnected data. Query an airport and get its timezone. Query a country and get its neighbors, currencies, and upcoming holidays. The relationships are built in and structured. Coverage includes 250+ countries with 5000+ regions, 316 IANA timezones, holidays for 230+ countries with regional breakdowns, 10,000+ airports, currencies, languages, and astronomy calculations (sunrise/sunset, golden hour, moon phases). Free tier available with 60 requests/day, and paid plans include more usage at a lower cost than competitors.