A standard for putting geographic data into a computer file is called a GIS FILE FORMAT. Dozens of formats have been developed since the 1970s for a variety of uses based on different data models. Government mapping organizations, GIS software providers, standards organizations, unofficial user communities, and even lone developers have all contributed to their creation.
In the 1960s, custom software underpinned the earliest GIS installations, which kept data in custom file formats. In the 1970s and early 1980s, general-purpose GIS software was created, with each package based on a proprietary file format. The global spread of GIS and the requirement for data sharing resulted in the demand for standard formats and interoperable data. The U.S. Spatial Data Transfer Standard was one of the first attempts at standardization. With the release of the Esri Shapefile format, the most widely used de facto standard for data sharing was established. The integration of spatial data in any format has been made much easier by free and open-source software libraries like the Geospatial Data Abstraction Library (GDAL). There have been more and more new file formats created, particularly with the rise of web mapping.
Purposes of GIS Files
Let’s examine the purposes of GIS files.
- For usage in geographic information systems (GIS) and other geospatial applications, a standard for encoding geographic data into computer files is known as a GIS FILE FORMAT.
- Numerous formats have been developed for a variety of uses based on different data models since the 1970s.
- Government mapping organizations, GIS software providers, standards organizations, unofficial user groups, and independent developers all use GIS files.
- Standardization initiatives like the Open Geospatial Consortium and the U.S. Spatial Data Transfer uniform were prompted by the need for interoperable data and uniform formats.
- Spatial data, including remote sensing imagery, topography and elevation data, population density, meteorological and climate information, and more, can be exchanged and stored using GIS files.
- GIS files are available in both raster and vector formats, each with unique benefits and drawbacks.
- Vector formats include Shapefile, GeoJSON, GML, and more, while raster formats include GeoTIFF, Esri grid, JPEG2000, and more.
Opening a GIS File
Now let’s explore opening a GIS file.
- You can download the compressed shapefiles by clicking on the file name, saving it to your local drive, and then unzipping it. The shapefiles were compressed using a zip program. (Depending on your browser, saving to disk can just need selecting "Save As.." from the "File" menu of the browser or answering a request).
- Once the file is on your local drive, double-click it to extract the shape files with your preferred unzipping program.
- ArcGIS and ArcGIS Explorer can be used to read the shapefiles once they have been downloaded.
- It is also possible to add the zipped shapefiles straight into ArcGIS Online.