Raster data can be clipped by another raster data, graphic or polygon feature. This tutorial shows how to clip one raster data with polygon feature (shapefile) in ArcGIS 10.
1. Open ArcMap, add raster data and polygon
2. If polygon consists of several feature, do SELECT feature which is going to be used to clip the raster data (like on the picture above).
3. Run ArcToolbox > Spatial Analyst Tools > Extraction > Extract by Mask
4. Select Raster input and feature input
5. Execute the tool
6. Here is the result
