Bollywood is the nickname given to the Indian film industry - it's a play on the word Hollywood.
The B comes from Bombay (also known as Mumbai), a big city in India.
Bollywood is massive. It makes up to 800 films a year - twice as many as Hollywood and about 14 million Indian people go to the cinema everyday
Films are made so fast that sometimes actors on set shoot scenes for four different films at a time - using the same actors and the same backgrounds. And sometimes the scripts are even hand-written!