Gpsd is a user land daemon acting as a liason between a gps or
Loran-C receiver and clients. The receiver is expected to generate
position information as NMEA-0183 sentences, or Rockwell binary format,
although that can be changed.

Gpsd listens on port 2947 for clients requesting position, time,
velocity or altitude information.

Gpsd can take information from the gps and translate it into
something easier to understand for clients.