Cold Start, Hot Start, Warm Start

Cold start: GNSS products start up in a state where the ephemeris, almanac, approximate time, and approximate location are unknown.
Warm start: GNSS products start up in a state where the ephemeris is unknown, the almanac, approximate time, and approximate location are known.
Hot start: GNSS products start up in a state where the ephemeris, almanac, approximate time, and approximate location are known.