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Shapefile

Shapefile Components 🔹 .shp — Geometry file What it contains: • The actual geographic shapes (points, lines, polygons) Examples: • City locations (points) • Roads (lines) • Administrative boundaries (polygons) 📌 This is the core file — without it, there is no map. ⸻ 🔹 .shx — Shape index file What it contains: • An index of the geometry file • Allows fast access to shapes 📌 Improves performance when loading and navigating data. ⸻ 🔹 .dbf — Attribute table What it contains: • Attribute data linked to each shape • Stored in dBASE format Examples: • Name, population, area, ID • Road type, length, category 📌 Each row corresponds to one geometry in the .shp file. ⸻ 🔹 .prj — Projection file What it contains: • Coordinate Reference System (CRS) information • Projection, datum, units 📌 Without this file, GIS software does not know where the data is on Earth. ⸻ 🧩 Optional (But Common) Shapefile Files 🔹 .cpg — Character encoding What it contains: • Text encoding for the .dbf file (UTF-8, Latin1, etc.) 📌 Prevents issues with special characters and accents. ⸻ 🔹 .sbn / .sbx — Spatial index files What they contain: • Spatial indexing for faster rendering and queries 📌 Automatically created by some GIS software. ⸻ 🔹 .xml — Metadata file What it contains: • Dataset description • Source, author, creation date, data quality

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