日本海 (Nihonkai), or the Sea of Japan, is a marginal sea located between the Japanese archipelago and the Asian continent. It is bordered by several countries, including Japan, South Korea, North Korea, and Russia. The sea is known for its rich marine biodiversity and is an important fishing ground. The Sea of Japan has a unique geography, featuring deep basins and numerous islands, such as Sado Island and Okinoshima. It plays a significant role in regional climate patterns and is influenced by ocean currents, including the Kuroshio Current. The sea is also vital for trade and transportation in the region.