Introduction to Digital EarthUS Vice President Al Gore, January 31, 1998 California Science Center in the United States delivered a speech entitled "Digital Earth: Understanding our planet in the twenty-first century approach" the official presentation of the "Digital Earth" Gore's report points out that: a new wave of technological innovation is to allow people to access, storage, processing and display of the Earth's vast data of unprecedented and wide-ranging and diverse environmental and cultural data; and most of such data is "the light of the geographical coordinates", that is, the geographical location of data on the Earth's surface by reference to a specific location; and now the difficulty lies in how to take full advantage of these vast data, which is how these data become meaningful, that is, to raw data into comprehensible Today, we often find a lot of data, but I do not know how to deal One example can illustrate this Satellite is designed to help human beings we understand the global environment, it will be in two weeks filming the Earth's surface again, the United States continued to collect image data for more than two decades of history; but the vast majority of these images is still quiet lying electronic data As the United States for a period of time over the past agricultural policy, on the one hand, the production of food was piled up in the Midwest rotten food warehouse, on the other hand there are millions of people were starved to Now, it is greed and a thirst for knowledge, and a lot of information while it is idle, no one is