Well-Known Text (WKT) is a standard text format for representing spatial geometric objects and coordinate systems in GIS. WKT is a way of writing geometric shapes or coordinate systems in a text format that is both readable by human and machine.
This standard is established by the Open Geospatial Consortium (OGC).
Why is WKT important in GIS?
WKT is used because it is:
✔ Portable (across GIS software: QGIS, ArcGIS, PostGIS, R, Python)
✔ Readable (easy for humans to read)
✔ International standard
✔ Easy to store (database, CSV, SQL)
Many systems store geometry not as images, but as WKT text or binary (WKB) data.
Types of GIS Reference Systems
A. Geometry Reference Systems
Used to represent the shape of spatial objects.
Geometry Type: Function
POINT: Point
LINESTRING: Line
POLYGON: Area
MULTIPOINT: Multiple points
MULTILINESTRING: Multiple lines
MULTIPOLYGON: Multiple polygons
GEOMETRYCOLLECTION: Geometry collection
| Type | Function |
POINT | point |
| LINESTRING | Line |
| POLYGON | Area |
| MULTIPOINT | poly dots |
| MULTILINESTRING | poly lines |
| MULTIPOLYGON | poly polygon |
| GEOMETRYCOLLECTION | Geometry Collection |
B. Coordinate System Reference Systems (CRS)
Used to define a Coordinate Reference System (CRS). Example: EPSG: 4326 (WGS84), UTM: Local projection.
