Thanks to this world map that shows the density of people with the surname Yau in different countries, you can get an idea not only of the popularity of the surname Yau in each country but also of the different migrations of people surnamed Yau.
The quantity of people with the surname Yau that we can find in each country can help us discern the origin of the surname Yau, as logic tells us that the place with the most people surnamed Yau will be the country or area of origin of the surname Yau.