Is it better to turn off your laptop than just close it?

I just got my own computer and I am trying to conserve the battery as long as I can. I have heard that you can just close it or sleep it and it stays on with very little battery, but other people say it is best to shut it down when you are not using it. It is much easier to just close it, but I have been turning it off just to be safe- but do I have to?