Using Spatial Analyst
This section introduces the main types of analyses that you can perform on the cell-based data or raster data model using the ArcGIS Spatial Analyst extension. The Esri GIS Dictionary defines the raster as "an array of equally-sized cells arranged in rows and columns, and composed of single or multiple bands" (A to Z GIS: An Illustrated Dictionary of Geographic Information Systems, Tasha Wade and Shelly Sommer, Esri Press). The raster data represents a feature through a squared cell (or pixel), or a group of squared cells (pixels) with the same attribute value. The size of a cell defines the spatial resolution of a raster. A raster with small cells has a higher resolution, while a raster with large cells has a lower resolution. A raster can be stored as follows:
It can be stored as a raster dataset inside a geodatabase.
Outside a geodatabase, it can be stored as a raster dataset on disk. It may be stored in many formats, such as ESRI Grid, TIFF, JPEG, MrSID (Multiresolution...