At the time of writing there where various methods to store location information for nodes (location, CCK Latitude Longitude, GeoLocation, etc). there were no modules to store lists of co-ordinates that could be combined to make tracks.
The initial goal of the project was to be able to render altitude profiles for mountain bike rides. At the same time I realised that in order to make the module as flexible as possible it should be able to store arbitrary information for each point (user data such as heart rate for athletes) and be flexible in the details required and stored for each point.
Currently the module only understands distance and altitude, the database structure is there for user data but not yet implemented. Using the bundled trackfield_graph module data can only be graphed with distance as the X-axis but support for time along that axis is a goal.