Land surveyors once used tape measures and transits to measure distances and positions Since the 1980s, electronic distance measurement, or EDM, devices have allowed for a lot more efficient and accurate measurements These use a wave of energy that's shot between the EDM instrument and a reflector Enough time the beam takes to return is then calculated as distance Today, such calculations can be done using sophisticated GPS systems
 
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 The Global Positioning System uses a network of satellites to precisely pinpoint the device's location on the planet at at any time GPS uses the principle of trilateration, utilizing the location of several satellites to pinpoint a precise location A receiver can determine the latitude, longitude, and elevation of a point using four or more satellites; there are a total of 24 Global Positioning System satellites currently used First developed by the US  https//propertyinspectionsnwcom/  of Defense as a navigational aid in 1994, today it is used in many devices, tracking from mobile phones and delivery vehicles to the movement of the tectonic plates of Earth's crust
 
 Land surveyors use Global Position Systems to note the complete coordinates of spatial locations Exact measurement of these positions is one of the fundamental components of land surveying The benefit of is that it is much more accurate than hand-measuring these locations There is some degree of error in all land surveying measurements, due to human errors, environmental characteristics like variations in magnetic fields, temperature, and gravity, and instrument errors GPS allows for a lot more precise measurements than previously open to land surveyors using measuring tape and an angle sight
 
 Another benefit of the use of its use as a land surveyor is that the coordinates could be located precisely, while other methods of land surveying rely on measurements from other known locations, like the edge of the property line, the corner of a house, or another landmark These locations could change over time, such as if a house is torn down or another obstacle is built between your structure and the measured point; a good surveyor's stake could be removed before the land is re-surveyed The coordinate of confirmed location on the planet, however, remains the same Therefore, using GPS as a land surveyor produces measurements which will be accurate regardless of what happens to the encompassing land
 
 Although Global Position System receivers allow for very precise measurements, there is still a qualification of error involved A receiver on a tripod will record the location slightly differently every time; when many measurements are taken, these data points will form a cluster around the actual location Better-quality receivers, of course, reduce this amount of error Survey-grade receivers, rather than those meant for non-surveying uses, may produce a group of measurements clustered in a matter of one centimeter of the specific location Today's receivers are steadily gaining in use, but might not be as accurate as the surveyor would like, especially in areas which are heavily wooded or which have other large obstructions However, the technology is rapidly advancing and gaining a foothold in the available equipment for land surveyors Since 1994, the accuracy available when working with GPS units has improved steadily