Kolkata, is the capital of the Indian state of West Bengal and was capital of British India until 1912. The city's name was officially changed from Calcutta to Kolkata in January 2001. Despite the new name being phonetically closer to the Bengali version, many people and organizations still refer to it as Calcutta. In Hindi, the city is referred to as Kalkatta.

Kolkata also refers to the name of the Kolkata administrative district of West Bengal that part of the city lies in. The urban agglomeration of Kolkata covers several municipal corporations, municipalities, city boards and villages and is the third largest urban agglomeration in India after Mumbai and Delhi. As per the census of 2001, the urban agglomeration's population was 13,216,546 while that of the city (Municipal Corporation of Kolkata) was 4,580,544. Kolkata city's population growth has been pretty low in the last decade.

The city is situated on the banks of the Hoogli River (a distributary of the Ganges). Some of the renowned engineering marvels associated with Kolkata include the bridges that span across this river to its twin city of Howrah (which is routinely considered as part of greater Kolkata): the Howrah Bridge (Rabindra Setu), Vivekananda Setu and Vidyasagar Setu.