Japan (日本, Nihon or Nippon^?, officially 日本国 Nippon-koku or Nihon-koku) is an island country in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south. The characters which make up Japan's name mean "sun-origin", which is why Japan is sometimes identified as the "Land of the Rising Sun".

Japan is an archipelago of 6,852 islands. The four largest islands are Honshū, Hokkaidō, Kyūshū and Shikoku, together accounting for 97% of Japan's land area. Most of the islands are mountainous, many volcanic; for example, Japan’s highest peak, Mount Fuji, is a volcano. Japan has the world's tenth-largest population, with about 128 million people. The Greater Tokyo Area, which includes the de facto capital city of Tokyo and several surrounding prefectures, is the largest metropolitan area in the world, with over 30 million residents.

Tokyo (東京, Tōkyō; "Eastern Capital"^?), officially Tokyo Metropolis (東京都, Tōkyō-to^?), is the capital and largest city of Japan, and is one of the 47 prefectures of Japan. It is located on the eastern side of the main island Honshū. Tokyo's government also administers the twenty-three special wards of Tokyo, each governed as a city, that cover the area that was once the city of Tokyo in the eastern part of the prefecture.

The population of the special wards is over 8 million people, with the total population of the prefecture exceeding 12 million. The prefecture is the center of the Greater Tokyo Area, the world's most populous metropolitan area with 35 to 39 million people (depending on definition) and the world's largest metropolitan economy with a GDP of US$1.479 trillion at purchasing power parity in 2008.