If you are new to using GIS software or a casual user you may be surprised to learn that standard formats such as shape files do not contain sufficient information for successfully transferring data between systems.

For instance if you have been sent some shape files together with how they should appear in your system, and you are presented with something different when they are loaded, there is a simple explanation.

Here is a screen shot of how two layers should display in your system.

And here is how it may look if loaded in just a default shape format.

The Microsoft windows file management system was developed to enable users to easily save, copy, delete and move files within a hierarchical folder structure. Each file type is identified by a dot definition system. So a Paint program file could have a .png, bmp or .gif format. A text file could have a. .doc format.  An excel spreadsheet could have a ,xls format. This file management system works very well for file types which generally consist of a single file format, however GIS formats such as Esri shape files or MapInfo tab files are made up of a number of different file types. This often presents a problem for casual GIS users when copying, deleting, moving or saving such files through a file management system such as Microsoft Windows. Often only the .tab or shp file element is copied which means that the specified file will not load into a GIS system.

In the above screen shot from the Windows file management system the shape file format can be seen to consist of four files, all of which are needed to produce a map layer in a GIS.

ESRI have addressed this problem with the introduction of ArcCatalog, which is there own proprietary file management system. Within ArcCatalog various filetypes are stored is such a way as to enable the user to access the various elements as if they were a single file. Additional features enable users to preview maps within ArcCatalog as well as the ability to drag and drop files into the map surface.