| A | B |
| Earth Science | the name for the group of sciences that deals with Earth and its neighbors in space |
| Geology | the study of Earth |
| Oceanography | the study of the composition and movements of seawater, as well as coastal processes, seafloor topography, and marine life |
| Meteorology | the study of the atmosphere and the processes that produce weather and climate |
| Astronomy | the study of the universe |
| Hydrosphere | the water portion of Earth |
| Atmosphere | the gaseous envelope of Earth |
| Geosphere | the layer of Earth under both the atmosphere and the oceans. It is composed of the core, the mantle, and the crust |
| Biosphere | the portion of Earth that contains all living things |
| Core | the innermost layer of Earth |
| Mantle | the relatively thick layer between the core and the crust |
| Crust | the thin, rocky outer layer of Earth |
| Latitude | The distance north or south of the equator, measured in degrees |
| Longitude | the distance east or west of the prime meridian, measured in degrees |
| Topographic map | represent Earth's three-dimensional surface in two dimensions. Show elevation of Earth's surface by means of contour lines |
| Contour line | a line on a topographic map that indicates elevation; every point along a contour line has the same elevation |
| Contour interval | tells the difference in elevation between adjacent contour lines on a topographic map |
| System | any size group of interacting parts that form a complex whole |
| Hypothesis | a possible explanation for a set of observations |
| Theory | a well tested and widely accepted idea that best explains certain observable facts |