What Is GeoJSON? A Practical Guide for Web Maps
GeoJSON is one of the most common formats for web maps. This guide explains points, lines, polygons, and properties.
Topic archive
Spatial Data
Practical notes about GeoJSON, CSV points, boundaries, coordinate formats, and data preparation.
How Points, Lines, and Polygons Work in Map Data
A practical introduction to the three basic geometry types behind many web maps and spatial data workflows.
CSV to Map: How Location Data Becomes a Web Map
Learn how a spreadsheet with place names or coordinates can become a usable map layer.
Administrative Boundaries Explained for Map Projects
Administrative boundaries are useful but easy to misunderstand. This guide explains how to use them carefully.
Common Coordinate System Mistakes in Web Mapping
A practical checklist for avoiding wrong locations, shifted points, mixed coordinate formats, and projection confusion.