Bollywood is the informal term popularly used for the Hindi-language film industry based in Mumbai (formerly known as Bombay), Maharashtra, India. The term is often incorrectly used to refer to the whole of Indian cinema; it is only a part of the total Indian film industry, which includes other production centres producing films in regional languages. Bollywood is the largest film producer in India and one of the largest centres of film production in the world.
Bollywood is formally referred to as Hindi cinema. There has been a growing presence of Indian English in dialogue and songs as well. It is common to see films that feature dialogue with English words (also known as Hinglish), phrases, or even whole sentences.