Best Way to Store GPS Coordinates? (What Data Type?)

I would suspect that the best way to store the data would be in the original NMEA format with which it is sent.

Actually the question is about the long/lat and it seems that the best format is to store them as floats and then transform the decimal degrees to other format if needed.

From all the software I use to manage gps coordinates, it seems the most used formats are .loc for simple waypoint name, longitude, latitude and .gpx for the same plus descriptions, pictures, files, and tons of other information.

it seems most downloads of coordinates come to me in one of these formats or are eventually converted to them.

both formats can be edited and manipulated with spreadsheet or text programs.

Here are some links to their descriptions.

.loc

and

.gpx

The .gpx files are also used by the Garmin line of gpsr's and I frequently use the drag and drop method to bring the files in and out of the Garmin units

If all you care about preserving is the long/lat I would use a pointf data type. It would save on memory and neatly encapsulate the data you wish to retain.