The line representing administrative boundary, which are recognised by governments or some other organizations for administrative purposes.The administrative boundaries range from large groups of nation states to small administrative districts and suburbs. They are filtered and simplied according to the tag 'admin_level', which goes from 1 to 10 with an indication of every level of importance. For many areas, the information on where exactly the border is, is not freely available to use. NOTE: As OSM only has “boundary ” showing up what type of the line, such as “Aministrative”,“National_Park”, “maritime” etc. It doesn't have column for determining “disputed”, we consider use NE data as country data for higher zoom levels.

The disputed value determined whether the administrative boundary are controversial. The two possible values are: '0' (verify) and '1' (disputed).

admin_level:

The maritime indicates a maritime administrative boundary.

The parent field is specified which country the boundary is belongs to.