From Destinypedia, the Destiny wiki
Destinations are locations that players can travel to from the Director. This primarily includes PvE locations and social spaces; Crucible locations are normally selected at random and cannot be visited during matchmaking except in private matches. PvE Destinations are the largest playable spaces and have a large number of activities available, namely: Patrol, Story Missions, Strikes, and Raids.
Note: Despite being separate from Mars, Phobos is accessible from the Meridian Bay map screen.
Vaulted Destinations are no longer accessible, but may still host Crucible or Gambit maps, and occasionally special PvE activities.
List of appearances