Osaka (大阪, Ōsaka?) listen (help·info) is a city in the Kansai region of Japan's main island of Honshu, a designated city under the Local Autonomy Law, the capital city of Osaka Prefecture and also the biggest part of Keihanshin area, which is represented by three major cities of Japan, Kyoto, Osaka and Kobe. Located at the mouth of the Yodo River on Osaka Bay, Osaka is the third largest city by population after Tokyo (special wards) and Yokohama.
Keihanshin is the second largest area in Japan by population and one of the largest metropolitan areas highly ranked in the world, with nearly 18 million people, and by GDP the second largest area in Japan and the seventh largest area in the world.
Historically the commercial centre of Japan, Osaka functions as one of the command centers for the Japanese economy. The ratio between daytime and night time population is 141%, the highest in Japan, highlighting its status as an economic center. Its nighttime population is 2.6 million, the third in the country, but in daytime the population surges to 3.7 million, second only after Tokyo (combining the Special wards of Tokyo, which is not a single incorporated city, for statistical purposes. See the Tokyo article for more information on the definition and makeup of Tokyo.) Osaka used to be referred to as the "nation's kitchen" (天下の台所, tenka no daidokoro?) in feudal Edo period because it was the centre of trading for rice, creating the first modern futures exchange market in the world.
Osaka Bay (大阪湾 Ōsaka-wan) is a bay in western Japan. As an eastern part of the Inland Sea, it is separated from the Pacific Ocean by the Kii Channel and from the neighbor western part of the Inland Sea by the Akashi Strait. Its western shore is formed by Awaji Island, and its northern and eastern shores are part of the Kansai metropolitan area.
Major ports on Osaka Bay include Osaka, Kobe, Nishinomiya, Sakai, Amagasaki, and Hannan.
A number of artificial islands have been created in Osaka Bay in past decades, including Kansai International Airport, Port Island, and Rokko Island.
Several islands at the south end of Osaka Bay are part of the Seto Inland Sea National Park.
Industries locate around Osaka Bay because there is a skilled and plentiful workforce, many port facilities, efficient linkages (from small to medium to large firms). There are good transport links (including the Shinkansen), room for expansion (land reclaimed form the sea), and a large local market (9 million).
There has been a recent economic change in Osaka Bay: The decline of older 'heavy' industries such as Nippon Steel, and the expansion of 'new tech' companies such as ICT. There has been a growth in the quaternary industries — research, development, and information. There has also been a development in the science parks and the building of new motorways; this has meant the loss of the countryside.