A montage sequence consists of a series of short shots that are edited into a sequence to condense narrative. It is usually used to advance the story as a whole (often to suggest the passage of time), rather than to create symbolic meaning. In many cases, a song plays in the background to enhance the mood or reinforce the message being conveyed. One famous example of montage was seen in the 1968 film 2001: A Space Odyssey, depicting the start of man's first development from apes to humans. Another example that is employed in many films is the sports montage. The sports montage shows the star athlete training over a period of time, each shot having more improvement than the last. Classic examples include Rocky and the Karate Kid.