Frankfurt am Main ( /ˈfræŋkfərt/; German pronunciation: [ˈfʁaŋkfʊɐt am ˈmaɪn] ( listen)), commonly known simply as Frankfurt, is the largest city in the German state of Hesse and the fifth-largest city in Germany, with a 2010 population of 688,249.[2] The urban area had an estimated population of 2,300,000 in 2010.[3] The city is at the centre of the larger Frankfurt Rhine-Main Metropolitan Region which has a population of 5,600,000[4] and is Germany's second-largest metropolitan region.

Frankfurt is the financial and transportation centre of Germany and the largest financial centre in continental Europe. It is seat of the European Central Bank, the German Federal Bank, the Frankfurt Stock Exchange and the Frankfurt Trade Fair, as well as several large commercial banks, e.g. Deutsche Bank, Commerzbank and DZ Bank. Frankfurt Airport is one of the world's busiest international airports, Frankfurt Central Station is one of the largest terminal stations in Europe, and the Frankfurter Kreuz is one of the most heavily used Autobahn interchanges in Europe. Frankfurt lies in the former American Occupation Zone of Germany, and it was formerly the headquarters city of the U.S. Army in Germany.

Frankfurt is considered an alpha world city as listed by the Loughborough University group's 2010 inventory,[5] was ranked 20th among global cities by Foreign Policy's 2010 Global Cities Index[6] and was ranked 6th among global cities for economic and social innovation by the 2thinknow Innovation Cities Index in 2010.[7]

Frankfurt is an international centre for commerce, finance, culture, transport, education, and tourism. According to the Mercer cost of living survey, Frankfurt is Germany’s second most expensive city, and the 48th most expensive in the world.[8] Frankfurt also ranks among the 10 most livable cities in the world according to Mercer Human Resource Consulting.[9]
Reference: http://en.wikipedia.org/wiki/Frankfurt%2C_Germany