Ōsaka (大阪) is the third largest city in Japan, with a population of over 2.5 million people in its greater metropolitan area. It is the central metropolis of the Kansai region and the largest of the Osaka-Kobe-Kyoto trio. If Tokyo is Japan's capital, one might call Osaka its anti-capital. Whatever you call it, though, there are many opportunities for you to discover its true character.
Veiled much with a commercial-centric city touch, you may as well start from picking up the lively intonation of Osaka dialect, heard from the people as you ride on the escalators standing on the right, instead of the left in Tokyo; then discovering the contrast of popular food to eastern Japan, as you look for places to lunch. The deeper you get inside, and at the end of your stay, it is not completely impossible that you may have compiled your own original list of reasons covering from history, culture, sports, to business. (Osaka Wikitravel)