Vector and Raster Maps: Differences and Uses

The data produced in mapping is usually in vector or raster format. These two data types directly affect how a map is stored, processed and analysed. So what is the difference between a vector map and a raster map, and which one is preferred for which projects? In this article we compare these two basic data models for surveying engineers and GIS users.

What Is a Vector Map?

Vector maps are made up of geometric shapes such as points, lines and polygons. Each feature has coordinate information and attribute data.

Examples:

Point → building, well, pole
Line → road, river, power line
Polygon → plot, parcel, lake

Advantages:

High accuracy.
Integrates easily with databases (e.g. land registry and parcel information).
Updating and editing are fast.

Disadvantages:

Less visual detail.
Processing time can grow in complex analyses.

What Is a Raster Map?

Raster maps are an image-based data model made up of pixels (grid cells). Each pixel holds a colour or numeric value for a location.

Examples:

Satellite images
Orthophoto maps
Digital elevation models (DEM, DSM)

Advantages:

Gives the visual representation closest to reality.
Ideal for surface analyses (slope, elevation, visibility).
Easy to interpret over large areas.

Disadvantages:

Large file sizes.
Not suitable for precise spatial measurements.

Differences Between Vector and Raster Maps

Feature	Vector map	Raster map
Data structure	Point, line, polygon	Pixel (grid)
Visual representation	Simple, schematic	Realistic, detailed
Type of analysis	Spatial analysis	Surface analysis
File size	Small	Large
Example use	Cadastre, infrastructure	Satellite, orthophoto

The difference between vector and raster data

Which One Should You Use When?

Vector map:

Cadastre, zoning plans, infrastructure projects
Ownership analysis, road planning

Raster map:

Satellite-based monitoring systems
Terrain model production
Visual mapping

Today, GIS (geographic information systems) applications usually use both kinds of data together. For example, a parcel vector is overlaid on an orthophoto raster, giving both spatial and visual accuracy.

Conclusion

Vector and raster maps are both essential parts of mapping. Vector has the advantage in precision and data structure, while raster is ideal for realistic visuals and surface analyses. Choosing the right data model for the project is critical for accuracy and efficiency.