Is there a legend that explains the meaning of colored geographical areas on Google Maps?

Question

Some colors are obvious, but some are not (at least to me). For example, what does it mean when an area is shaded pink?

Answer 1

http://searchengineland.com/google-maps-now-highlighting-borders-of-cities-postal-codes-more-108589

If I search by postal code, the area for that postal code has a pink outline, when zooming back, the whole section is covered in pink. Same thing for a City, or a county , state, or even country.
So any area that is a specific region for the search input it highlights in pink.

Some of the legend info varies on map type and region.