What kind of data format is most commonly used in raster overlays?

Raster overlays primarily utilize image data formats, as raster data is represented by a matrix of cells (or pixels) where each cell contains a specific value representing information such as temperature, elevation, land cover, or other continuous data. Image data can easily encapsulate this variation across a geographic area, allowing for effective analysis and manipulation in GIS.

In raster analysis, multiple layers of image data may be stacked and processed together to determine relationships, perform suitability analysis, or conduct visualizations. Raster datasets typically come from sources like satellite imagery, aerial photos, or digital elevation models (DEMs), all of which are inherently image data formats.

Other formats such as vector data, shapefiles, and point data belong to a different category of GIS data types. Vector data represents discrete features using points, lines, and polygons, which is distinct from the continuous representation of raster data. Shapefiles are a specific type of vector data and do not apply to raster overlays. Point data can represent single locations, typically not suitable for overlays that require covering an area, making image data the most relevant format for raster overlays.