If you are unlucky enough to die in a fight you lose everything.  Needless to
say it is a good idea to avoid dying.  If you die through any other act, such 
as an  avalanche or falling  off a cliff you will  lose all of your equipment 
and have to re-enter the game.

When you quit  your score is saved along  with your current statistics.  When
you re-enter the  game your score and  statistics are  restored and  you will
start back at the  beginning of the game with no equipment.  The ultimate aim
of the game is to become immortal.  As to how you achieve this is - well good
luck finding out.