Alpha islands are the high security zones, where PvP is prohibited (easily seen as blue "diodes" on Bot status), making these ideal for inexperienced Agents. Sometimes, even PvP hardened veterans are being seen there (especially during mining ops), since PvP prohibition allows them to work in relative peace.
There are 2 types of Alpha islands:
Alpha 1 islands all have a terminal and 3 outposts, this is where novice players start the game. New players start on New Virginia, regardless on the faction of their choosing during Virtual Training. All NPCs on this island don't attack other players unless targeted and locked (Orange NPC). New Virginia is connected via teleports to Alpha 2 Hershfield island.
Alpha 2 came at a later date during game's live development with the need for more space for players to roam, they only have one main terminal. NPCs are harder
and some (Red NPCs) shoot you, if you get too close. Resources are more abundant on these islands, with a full rack of 25 production points for all facilities at their main terminal with some faction-specific specialities up to 50. So far, only Hershfield is available.