This text aims to familiarize the uninitiated with satellite data and with the reading of colour-coded satellite images of the Earth. It gives a sense of how the raw data is converted into information about the Earth and the atmosphere, and shows the range of information being collected about the Earth through satellites. There is also coverage of six of the important topics in Earth/atmosphere studies now being examined with data from satellites: atmospheric ozone; polar sea ice; continental snow cover; sea surface temperatures; land vegetation; and volcanoes.