No one actually knows the exact purpose of the universe but there are a number of theories out there. Check out a video called "Does the Universe Have a Purpose? feat. Neil deGrasse Tyson" on YouTube, it is a short video narrated by Neil deGrasse Tyson on the minutephysics YouTube Channel.
Neil also has an interesting television documentary called Cosmos: A Spacetime Odyssey which you can find on YouTube and NetFlix.
