A raster layer is a layerA layer is a reference to a collection of geographic data that is used to access and display data. The data for layers are typically provided by the basemap layer service and data services.Learn more type that allows developers to display raster dataA raster is a matrix of cells (or pixels) organized into rows and columns (or a grid) where each cell contains a value representing information, such as temperature. Rasters include digital aerial photographs, imagery from satellites, digital pictures, and scanned maps.Learn more in their applications. A raster layer can render raster data from any type of raster. Raster layers can be added to a map as either a basemapA basemap is the foundational layer and data that provides the overall visual and geographic context for a map or scene. It typically includes geographic features and labels for land, water, roads, buildings, cities, places, and administrative boundaries, but can also include raster data such as satellite and areal images.Learn more or an operational layerAn operational layer is a layer used by a map or a scene to visualize geographic data. Operational layers are displayed on top of a basemap layer.Learn more.