Volcanology is a relatively new and intriguing field that studies one of the planet's most active processes: volcanoes. Volcanoes are studied by scientists from a variety of areas. Volcanologists who examine the processes and deposits of volcanic eruptions are known as physical volcanologists. Seismology (the study of earthquakes, which is especially valuable in volcano monitoring), gravity, magnetics, and other geophysical data are all studied by geophysicists. Geodesy is a branch of science that investigates changes in the earth's shape caused by volcanic activity or ground deformation. Geochemists are scientists who research volcanic products (rocks, gas, and lava), with specialties spanning from volcanic gases to large-scale whole-earth processes. Remote sensing of volcanic hazards (using satellites or remote cameras), mathematical modelling of volcanic processes, Geographic Information Systems (GIS) mapping, electronics development, computer programming, and hazards education are all areas where scientists specialise. Volcanologists commonly visit volcanoes, particularly those that are active, to monitor eruptions and collect eruptive products such as tephra (ash or pumice), rock, and lava samples. Forecasting eruptions is a major subject of research; while there is now no accurate means to do so, predicting volcanoes, like predicting earthquakes, might save countless lives.