Remote sensing is
||any observation made at a point removed from the object under investigation. More commonly it refers to observations of areas of land and water covering the earth by airplane or satellite.
||the process of observing, measuring and recording objects or events from a distance.
The term was coined in the early 1960s when data delivered by airborne sensors other than photographic cameras began to find broad application in the scientific and resource management communities.
Remote sensing involves collecting an image of a region on the Earth by one of two means: passive or active.