The line that is vertical, or up and down.
A meridian of longitude and a parallel of latitude are perpendicular at their intersection, forming a right angle.
The meridian of 82° west longitude crosses the territory of -- Canada -- the USA -- Cuba -- the Cayman Islands -- Panama -- (Antarctica -- not a country)
the longitide line that has the measurement 0degrees is called equator
A meridian of longitude and a parallel of latitude are perpendicular at their intersection, forming a right angle.
The meridian of 82° west longitude crosses the territory of -- Canada -- the USA -- Cuba -- the Cayman Islands -- Panama -- (Antarctica -- not a country)
The International Date Line follows the meridian of 180° longitude, roughly down the middle of the Pacific Ocean. To avoid crossing nations internally the line deviates around the far east of Russia and then around various island groups in the Pacific. These various deviations (east or west) generally accommodate the political and/or geo-economic affiliations of the affected islands.