The world's 197 sovereign flags fall into roughly six visual families. Vertical tricolours descend from the French revolutionary flag; horizontal tricolours trace to the 16th-century Dutch revolt and the Russian merchant flag. Pan-African flags carry red, gold, green, and sometimes black — descended from the continent's earliest independence flag and the Ethiopian tradition before it. Pan-Arab flags use red, white, black, and green, derived from the 1916 Arab Revolt. Pan-Slavic flags use red, white, and blue. The Nordic cross runs across Scandinavia, and the Southern Cross plus Union Jack motif clusters in Oceania.

This hub ships in two modes: multiple choice (see flag, pick from four country names) and type-in (see flag, type the country). 194 flags total — one flag's image asset is missing from the bucket at this writing and is temporarily excluded; the remaining states (minus the two partially-recognised states per long-standing quiz convention) are all covered.

Players who study the visual families can identify around 80% of world flags correctly. The hardest 20% tend to be the post-Soviet Central Asian states (all light blue with distinctive emblems but similar at a glance) and the Central American cluster (blue-white-blue horizontals with a central coat of arms).