Sensors are often used to automatically measure and record changes in conditions, such as:
- the temperature of a science experiment;
- the amount of light in a room;
- the level of noise being made by aircraft flying over a town.
It can sometimes be too difficult or dangerous for people to take measurements in certain places, so sensors are often used instead. Examples of remote sensing, where the measurements are sent over a long distance to a computer to be studied, include:
- weather forecasters who collect data from weather stations in remote areas to use in their forecasts;
- space researchers who send probes to survey other planets and send the data back to Earth using satellites to be examined by scientists.
The main disadvantage of remote sensing, however, is the initial cost of buying the equipment. For example, whilst a thermometer can be bought for about a pound, the cost of a good quality temperature sensor would likely be a lot more.