ESRI has a “GIS Best Practices” series that was launched last year to document successful case studies in a variety of industries.  The series continues to be added and contains essays on a variety of subject matters including public safety, conservation, and logistics.  The latest release is a compilation of past ArcNews articles entitled “Essays on Geography and GIS” and contains eleven articles beginning with a short “What is GIS” piece.  (Seen via All Points Blog).