Geographic Information Systems Basics

A geographic information system (GIS) is a computer system used to capture, store, query, analyze, and display geospatial data.

Components of a GIS include hardware, software, people, and organization.

The early 1960s saw the development of the Canada Geographic Information System, while the 1960s and 1970s witnessed advancements in computer mapping at institutions like the University of Edinburgh and Harvard.

Geospatial data refers to data that is location-specific and incorporates information about geographic features, such as roads, buildings, and land cover.

Data acquisition involves the process of obtaining geospatial data from various sources, including satellite imagery, aerial photographs, surveys, and GPS measurements.

Data that describes both the locations and characteristics of spatial features on Earth, like roads, land parcels, and vegetation stands.

A system that uses coordinates (like latitude and longitude) to locate points on the Earth's surface.

A system that converts the Earth's spherical coordinates into a flat, two-dimensional plane, allowing for easier measurement and analysis.

The process of transforming coordinates from the geographic coordinate system to the projected coordinate system, preserving shapes and distances as accurately as possible.

A data model that represents geographic features as points, lines, and polygons, with attributes assigned to each feature.

A data model that represents geographic features as grids of cells, where each cell has a specific value, typically representing a measurement or category.

The process of collecting geographic information from various sources, including satellites, aerial photography, and GPS devices.

The process of adjusting the position of geographic data to accurately align with a specific coordinate system, ensuring consistency across different datasets.

A data model that uses points and their x-, y-coordinates to represent features like roads, buildings, and rivers.

A data model that uses a grid of cells to represent continuous features like elevation and rainfall, where each cell has a specific value.

The process of transforming and correcting a map or image to align it with real-world coordinates.

The process of identifying and correcting errors in spatial data, such as inconsistencies in lines or overlaps.

A system used to manage and store attribute data in a GIS, usually in tables with columns and rows.

A GIS process that involves visualizing, manipulating, and querying data using maps, tables, and graphs.

Analysis techniques that focus on the immediate area surrounding a feature, such as calculating the distance to the nearest road.

Analysis techniques that consider a group of cells surrounding a central cell, like calculating the average elevation of surrounding cells.

Combining data from different layers (e.g., land use, roads) to create a new output layer.

Using the fixed cell locations of raster data (e.g., satellite images) to perform operations like adding or subtracting values.

A GIS technique that analyzes terrain features (e.g., slopes, elevation) and uses them to visualize and understand the landscape.

Using GIS to find areas visible from specific locations, helpful for planning cell towers or wildlife observation points.

A GIS technique used for tracking movement of water over a landscape and identifying watersheds.

A GIS technique used to estimate values at unknown locations based on known data points.

A GIS technique that uses locations to find things like closest hospitals or shortest routes.

Geographic information generated by the public using web applications and services, like OpenStreetMap.

A web portal providing access to geographic data and resources related to the U.S. Census Bureau.

A website dedicated to GIS and mapping tools that includes information on spatial analysis, data visualization, and geographic data management.

A software program developed by Autodesk that enables the creation and manipulation of 3D models within a geographic context, supporting the design and analysis of structures and other spatial elements.

A collaborative online platform used by researchers, organizations, and individuals to create and share geospatial data, enabling the visualization and analysis of geographic information for various purposes.

A web portal (developed by the U.S. government) offering access to geospatial information and tools for visualizing and analyzing spatial data, intended for a broad audience.

A service provided by Autodesk that facilitates the creation and manipulation of 3D models within a geographic context, supporting the design and analysis of structures and other spatial elements.

Software developed by Bentley Systems, Inc., that enables engineers, architects, and other professionals to create and edit geographic data, manage infrastructure projects, and perform various design and analysis tasks.

A software package developed by Caliper Corporation that focuses on transportation analysis and modeling, supporting the creation and manipulation of network data, travel demand forecasting, and route optimization.