I wanted a name for a repository to keep track of software I wanted to write to convert between different formats of GPS tracks. While my planned tools are only tangential to the idea of PNT defined by the US Government, it is a convenient TLA that I'm going to take advantage of.
I'm aware of a couple different formats for serializing GPS track information. Those are currently NMEA and GPX. The KML format contains the ability to define tracks as well. My plan is to create some tools for translating between the different formats for ingestion by other tools.