Watch Ricky Gervais explain atheism to Stephen Colbert. I like his explanation of the difference between science and religion. In fact, I like it so much I'm going to embellish it a bit and present it here ...Imagine what would happen after a giant meteor strike that wipes out everyone except for a small native tribe in the Andes that had no contact with other people before the apocalypse. All books and all knowledge will be destroyed.
Ten thousand years later there will be science books and they'll be pretty much the same as the ones we have now because people will simply rediscover the basic truths of nature. There might be religious books but they won't be anything like the holy books we have now because the people will have invented entirely new gods. That's the difference between science and religion.