Osaka is a city locate din the Kanai region of Japan. It is located on the mouth of the Yodo River on the main island of Hoshu. The city is the heart of Japan's 2nd largest metropolitan area. It used to be the commercial center of the country. As of January 2007, the area has an estimated population of close to 2.7 million people. The metropolitan region where Osaka belongs to has an estimated population of almost 18.7 Million people. Aside from being once the commercial capital of Japan, Osaka is also known as the 'Nation's Kitchen' or the 'Gourmet Capital of Japan'.

The city is also known for having a significant difference between its daytime and nighttime population. During the day the population in the city is at an average of 3.7 million. That number dramatically drops in the evenings to an average of 2.6 million with most of the daytime residents commuting out of the city.