Geographic information

Geographic information (also known as spatial or geospatial data) consist of descriptions of the characteristics of geographic phenomena (natural or man-made). These characteristics may include location, attributes, relationships with other phenomena, and how these characteristics change over time. Geographic information science is, therefore, the study of the collection, storage, integration, management, retrieval, display, analysis, and modeling of geographic information.

Objects
Geographic information can appear in a variety of forms, often dependent on the nature of the phenomena they describe. Discrete objects, such as buildings or roads, are typically described by a set of measured dimensions and consist of one or more shapes. Continuous phenomena or masses that are not discrete, such as a vegetation area, are represented by interpreted or estimated dimensions. For example, two ecologists could differ in what each considers the extent of an area of dense vegetation. This would result in two maps that display the same phenomenon (dense vegetation) with different dimensions.

Fields
Geographic information also includes the characteristics or properties of an object. These properties are called fields. Most fields are two-dimensional scalar fields, meaning they have a location and a value. Fields can range in type, from properties of natural phenomena (i.e. temperature) to calculated attributes (i.e. population density).

Displaying Geographic Information
Geographic information can be displayed or presented using multiple methods of delivery. The most common medium for displaying geographic information employs the discipline of cartography or mapmaking. Other mediums include tables, graphs, textual descriptions, databases, and digital deployment using the web.

The development of technologies such as remote sensing, Global Positioning System (GPS), and geographic information systems (GIS) have greatly enhanced the process of gathering, analyzing, and presenting geographic information.

Storing Geographic Information
Geographic information can be stored either physically or digitally. When done correctly, the storage of geographic information allows geographers to access information efficiently.

Physical Storage
Physical maps storing geographic information are typically placed in organized files and cabinets in libraries or map collections. An advantage to storing maps physically is that the information can be accessed without a computer, and the information is not susceptible to computer error (corrupt files, battery life, unauthorized access).

Digital Storage
Digitally stored geographic information can be saved onto a hard disk drive (HDD), flash storage device, magnetic disk (CD), or network in a file format that fits the geographers needs. Commonly used file formats for geographic data include: SHP (Shapefile), KMZ/KML (Keyhole Markup Language), GDB (File Geodatabase), LYR (Layer), OSM (OpenStreetMap).