Data sets can be quite simple, but in most cases will include one or more of the following
Vector data
- a polygon file (in Map Maker this is a .dra file in Arc this is a .shp)
- a database file (a .dbf file)
depending on where the data were sourced you may have a collection of other files. Do not edit these or try to open them.
Raster Data
- an image file (typically .tif or .jpg a picture file)
- a world file (.tfw or .jgw contains the geo-referencing co-ordinates without which your .tif file cannot be tiled correctly)
Again there may be a guddle of files in addition to these. I most cases they do no harm, so leave them alone.
In addition to the basic data files, there may be project files:
- .geo files are created by Map Maker
- .axl files are created
When you make a map, for printing or web publication you may want a legend and a key. In Map Maker this information is stored separately. Template files (for printing) are also stored separately.
It is therefore important that you keep your own project data well-organised. Try and keep all the files you are creating in your own personal space or you may find it gets abused by someone else sharing the same data sets.
You may also create a number of working files when making maps from scratch or annotating maps. When using Map Maker it is wise to save working copies frequently and incrementally. In other words using a version number to create a new copy every so often or on every save, if you are really paranoid. This should be a feature really and there should be an decent layer save function.