GIS Glossary

A unique identifier for each record in a GIS attribute table, essential for data integration and relational database management (inferred from standard GIS usage).

Coordinates that represent locations on a flat, two-dimensional surface, derived from a map projection.

The mathematical transformation of the earth’s curved surface onto a flat map, essential for accurate spatial analysis and measurement (inferred from standard GIS usage).

A file that stores the coordinate system and projection information for spatial datasets (inferred from standard GIS usage).

The process of analysing spatial relationships based on distance, such as identifying features within a certain radius of a point (inferred from standard GIS usage).

A widely used programming language in GIS for automating spatial analysis, data manipulation, and visualization tasks through libraries like GeoPandas and PySAL.

A free and open-source GIS platform widely used for spatial data analysis, mapping, and visualization. It supports a broad range of spatial data formats and analytical tools.

A standard area, often used in mapping (such as USGS topographic maps), defined by lines of latitude and longitude. Quadrangles are important for organizing and referencing spatial data.

One of four sections into which a plane is divided by two perpendicular axes, often used in spatial sampling or analysis.

A defined area used for sampling or analysing spatial patterns, especially in ecological or environmental studies.

A statistical method for studying the distribution of spatial features by dividing the study area into quadrats and analysing the frequency of features within each.

A spatial indexing structure that recursively divides a dataset (such as a raster image) into square cells of varying sizes until each cell is homogeneous. Quadtrees are used for efficient storage, retrieval, and analysis of raster and vector spatial data.

The examination of non-numeric spatial data, such as categories or descriptive attributes, to interpret spatial patterns or relationships.

Processes and procedures to ensure the accuracy, consistency, and reliability of spatial data and analysis results.

A core GIS operation that searches spatial or attribute data based on user-defined criteria, producing a subset of records for further analysis. Queries are essential for data selection, filtering, and spatial analysis.

An open-source programming language and software environment widely used for statistical computing and spatial data analysis, with extensive packages for GIS, such as sf, terra, and sp.

The selection of spatial features or locations at random for unbiased statistical analysis or ground truthing (inferred from standard GIS usage).

The difference between the maximum and minimum values of a dataset, used in spatial statistics and data normalization (inferred from standard GIS usage).

A spatial data model representing the world as a grid of equally sized cells (pixels), each with a value for a specific attribute (e.g., elevation, temperature, land cover). Raster data is fundamental for continuous data analysis and remote sensing.

A table storing attribute information for the unique values in a raster dataset, supporting classification and analysis (inferred from standard GIS usage).