Short answer: The FIFA World Cup is the global men's national-team football championship, held every four years.
Football's biggest tournament. Brazil leads all-time titles (5). Argentina (3, latest 2022), Italy (4, latest 2006), Germany (4, latest 2014), France (2, latest 2018), Uruguay (2), England (1), Spain (1). The 2026 World Cup is in USA/Mexico/Canada — 48 teams.