GML

Definition

GML, or Geography Markup Language, is an XML-based language designed for expressing geographical features and their attributes. It enables the exchange of geographic information across different systems and applications, making it essential for data interoperability in geospatial contexts. GML provides a standardized way to represent geographic data, ensuring that it can be easily shared and understood by various software tools and platforms.

5 Must Know Facts For Your Next Test

1. GML is maintained by the Open Geospatial Consortium (OGC), which ensures its continued relevance and evolution within the geospatial community.
2. It can represent both simple geographic features (like points and lines) and complex geometries (like polygons and 3D objects), making it highly versatile.
3. GML supports various coordinate reference systems, allowing for accurate representation of features in different geographic contexts.
4. Due to its XML basis, GML files can be easily integrated with web technologies and other data formats, enhancing their usability in web applications.
5. GML plays a crucial role in facilitating interoperability among diverse geospatial applications, as it allows different systems to understand and process geographic data consistently.

Review Questions

• How does GML facilitate data interoperability in geospatial applications?
  • GML facilitates data interoperability by providing a standardized format for representing geographic features and their attributes using XML. This means that different software tools and systems can read and understand GML data regardless of their underlying architecture. As a result, GML allows for seamless data exchange among diverse applications, which is critical in projects that require collaboration between different stakeholders in the geospatial domain.
• In what ways does GML enhance the functionality of Web Feature Services (WFS)?
  • GML enhances the functionality of Web Feature Services (WFS) by providing a common format for encoding geospatial features that are served over the web. When a WFS request is made, the response can be delivered in GML format, allowing clients to access detailed descriptions of geographic features. This integration means users can perform spatial queries and retrieve complex geospatial data while ensuring compatibility with various GIS applications that support GML.
• Evaluate the impact of GML on Spatial Data Infrastructure (SDI) initiatives globally.
  • GML significantly impacts Spatial Data Infrastructure (SDI) initiatives by promoting standardization and interoperability among diverse geospatial datasets. By adopting GML as a common format for sharing geographic information, SDIs can enhance collaboration between governments, organizations, and businesses. This leads to improved decision-making processes based on accurate spatial data, fosters innovation through accessible datasets, and ultimately contributes to more effective resource management and urban planning on a global scale.

Related terms

XML: XML, or eXtensible Markup Language, is a markup language used to encode documents in a format that is both human-readable and machine-readable, serving as the foundation for GML.

WFS:

Web Feature Service (WFS) is a standard protocol for serving geospatial features over the web, allowing clients to perform spatial queries and retrieve data in GML format.

SDI:

Spatial Data Infrastructure (SDI) refers to the framework of technologies, policies, and standards that facilitate the collection, sharing, and use of spatial data, often utilizing GML for data interoperability.