What defines raster resolution in GIS?

Raster resolution in GIS is primarily defined by the size of the raster grid cell. This cell size determines the spatial resolution of the data, which dictates how much detail is captured in the raster dataset. Smaller grid cells can capture finer details and variations in the landscape, whereas larger cells may oversimplify the representation and miss important features.

For example, a raster layer that represents terrain elevation with a grid cell size of 30 meters can provide a different level of detail compared to one with a cell size of 10 meters. This distinction highlights the importance of raster resolution in applications such as remote sensing, land cover analysis, and ecological studies, where precise spatial patterns are critical for accurate interpretation and analysis.

The other options, while related to raster data in some contexts, do not define raster resolution itself. The total area represented by the raster does not account for the resolution or detail of the data but merely describes the extent covered. The number of colors used in the raster pertains more to image quality or depth than to resolution. The level of detail in vector data is a separate concept, focusing on vector representations rather than raster formats. Thus, the size of the raster grid cell is key to understanding resolution within raster datasets.