Available with Spatial Analyst license.
Before beginning to perform analysis, it is important to understand the geoprocessing analysis environment within which you are working. The analysis environment includes the workspace into which results will be placed and the extent, cell size, and coordinate system of results.
When running geoprocessing tools, you can specify environment settings via the Environment Settings. You can override the default settings of the environments at various levels. Each tool dialog box has an Environments button that allows application-level settings to be overridden.
Some environments will be conditionally supported, depending on the input format, the output format, settings made in the parameters for a tool, and particular behaviors for that tool.
For more information on the specific environments that influence the analysis, see Analysis environments and Spatial Analyst.