A scheme for classifying advanced technological civilizations proposed by Nikolai Kardashev1 in 1964. He identified three high-level types and defined a logarithmic scale in terms of the power they could muster for the purpose of interstellar communications.

1. Able to harness all of the power available on a single planet. (Estimated 10^16 watts)
2. Able to harness all of the power available from a single star. (Estimated 10^26 watts)
3. Able to harness all of the power available from a single galaxy. (Estimated 10^36 watts)

Around five exabytes (5 billion gigabytes) of information was created in 2002, up from around two exabytes in 1999, according to the latest “How Much Information?” survey produced by the School of Information Management and Systems at the University of California in Berkeley. This is equivalent to half a million libraries the size of America's Library of Congress, or about 800 megabytes per person per year.

The human brain is the most complex object we are aware of in the universe, and not the least of its many remarkable achievements is the partial elucidation of its own working.
- Ian Glynn

Ever wanted to wish upon a star? Well, you have 70,000 million million million to choose from. That's the total number of stars in the known universe, according to a study by Australian astronomers. It's also about 10 times as many stars as grains of sand on all the world's beaches and deserts.