Karachi ( , ; ) is the largest city, main seaport and the main financial centre of Pakistan, as well as the capital of the province of Sindh. The city has an estimated population of 13 to 20 million, while the total metropolitan area has a population of over 25 million. Karachi is the most populous city in the country, one of the world's largest cities in terms of population and also the 10th largest urban agglomeration in the world. It is Pakistan's premier centre of banking, industry, economic activity and trade and is home to Pakistan's largest corporations, including those involved in textiles, shipping, automotive industry, entertainment, the arts, fashion, advertising, publishing, software development and medical research. The city is a major hub of higher education in South Asia and the wider Muslim world.
Karachi is ranked as a Beta world city. It was the original capital of Pakistan until the construction of Islamabad and is the location of the Port of Karachi and Port Bin Qasim, two of the region's largest and busiest ports. After the independence of Pakistan, the city population increased dramatically when hundreds of thousands of Urdu-speaking migrants or Muhajirs from India and other parts of South Asia came to settle in Karachi.
The city is located in the south of the country, along the coastline meeting the Arabian Sea. It is spread over 3527 km2 (3527000000 m2) in area, almost four times bigger than Hong Kong. It is locally known whom date=October 2011 as the "City of Lights" ( ) and "The bride of the cities" ( ) for its liveliness, and the "City of the Quaid" ( ), having been the birth and burial place of Quaid-e-Azam (Muhammad Ali Jinnah), the founder of Pakistan, who made the city his home after Pakistan's independence from the British Raj on 14 August 1947.