GPS recommended minimum

Most  GPS devices embedded in mobiles like the Nokia N810 output
something called the Recommended Minimum sentence C ($GPRMC).
http://www.gpsinformation.org/dale/nmea.htm#RMC

I think GGA is also very common, though most device drivers filter GGA
(and other lines) and expose only RMC.
http://www.gpsinformation.org/dale/nmea.htm#GGA

RMC is the minimum standard defined by
http://en.wikipedia.org/wiki/NMEA which a device must support to be
considered 'a GPS device'.

http://aprs.gids.nl/nmea/#rmc
http://answers.yahoo.com/question/index?qid=20080109031033AAkHMFQ


Kind regards from Surrey,