Explanation:

The International Date Line is an imaginary Line on the 180th meridian in the Pacific Ocean that goes through the Bering Strait (between Alaska and Russia), which is half way around the world from Greenwich, England. It is basically a straight Line; however, there are some zigzags. These zigzags are necessary because otherwise one country would be observing two Dates at the same time. In order to prevent this, the International Date Line curves around these countries and only goes through the Pacific Ocean