Geo data is a broad term that is used to describe sets of information that are used to define a geographic location on the surface of the earth. Several different types of data are available. Each set is normally designed for certain geographical information systems (GIS). The data could be very specific or it could be very vague depending on the purpose of the information. The most accurate information is gathered by professionals with surveying equipment and the assistance of satellites. Less specific information is still useful in systems that are more general or less scientific.
Types Of Data
There are several different ways that geo data can be defined. A very common dataset will include the latitude and longitude of a single specific location. This is often accompanied by an elevation in relation to sea level. Another way to define this type of data is geometrically. A vector that defines a location and direction is often used to describe a street. A dataset could also be collected that is relative to a defined space instead of being globally positioned with absolute coordinates. The dataset might use polygons to specific a location. This is done because many objects or structures on the earth occupy more than a single dot. A polygon could be used to describe the boundaries of a park, city block or country. There are currently several different standards for the data although there is no single worldwide format.
Nearly all geo data is accompanied by additional pieces of information known as metadata. The metadata that is included is usually focused on specific properties of a location that are useful for a particular industry or GIS. Each piece of metadata is attached to the coordinates or other location data in the database. This metadata could include the soil type, average wind speeds or average population. It could also include climate data such as the average rainfall or average temperatures. The format and type of metadata that is included will only be useful when it is processed by a GIS that has been designed to incorporate or read that information.
A major issue that must be dealt with when coding geographical locations is accuracy. The accuracy of a position can be affected by several factors. There are natural distortions because of the curvature of the planet. There are precision problems with floating point numbers since a GIS might round unusually long numbers down to an inaccurate figure. Issues with accuracy only become significant when databases are exchanged between different systems that were not specifically designed to handle the format.
The information that is gathered in a geo database has many uses. Scientifically accurate data is often used by engineers performing city planning and other large-scale construction projects. Global positioning systems (GPS) are a form of GIS that is designed to generate real-time maps for navigation. An increasing number of mobile devices and cell phones are including this type of data in order to provide localized services to individuals based on position. Delivery services around the world use geocoding on packages in order to locate destinations accurately. There are even handheld gaming units that use geo databases in order to determine if there are other players within the vicinity.