40. Relation Ogni oggetto può avere dei tag key=value node place = city name = Perugia population = 149125 is_in = Umbria, Italy way highway = primary name = Via Cassia ref = SS2 bridge = true
free-form tagging – Germans always want strict rules! GIS standards are often head-strong, complex; difficult for the masses to work with (think army of school children!)
“ tags” being somewhat of a misnomer since they are key=value while today the word is usually reserved for something one-dimensional!
![OpenStreetMap – cos'è? ,[object Object]](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)