Your ship should only be attacked in certain zones, which is around the PvP objectives called Cosmpiercers, and you'll see a message pop up if you enter one of those zones. Technically, you can be attacked anywhere, but most will not bother you. An exception to this is bounty hunters, but again, you'll receive a notification if someone has placed a bounty on you and they must have a valid RP reason for placing that bounty.
When your ship is destroyed, it will drop all cargo it currently has and anyone can salvage that. Vast majority of players will return this to you, exceptions might be any PvP kills, which are extremely rare.
As far as ground theft is concerned, only the nanoseer comes close to being able to do this and even then, they can't steal your money.
Both kinds of PVP are restricted to specific PVP zones except when done for good RP reasons. If you get killed on the ground, the other guy can steal your junk items (the stuff you sell at junk shops for cash) and your INR (the thing you can grab from your corpse to recover XP after dying) but will not get your armour, weapons or other inventory items. Theft skills aren't a thing. If you get killed in space PVP, all of your current cargo drops (and will probably get stolen), but the ship itself will get replaced by ship insurance.
E: Candyfloss above is incorrect on a couple points. Nanoseers can't force you to give items (that was removed early on in the beta), and you can't be attacked in your ship for no reason outside of PVP zones - there was a news post to that effect by the admins clarifying the topic. Finally, Cosmpiercers aren't the only ship PVP zones; pirate refineries are also open PK.
The ground PvP areas are called Caches and are announced on the CONFLICT channel. These aren't places you can just wander into, at the location will the option to ENTER CACHE and once inside it is open PK territory. Even then, there aren't many players who will PK a newbie just for being in a cache unless it's in a group setting. So you're good!!
You can set your status to Lawless if you want PK anywhere. Even if you do, you probably won't see much combat. I've had lawless on for almost 2 years and only been in a couple of fights outside of Caches or the Arena. The lack of random griefing is nice, as is the lack of item theft, outside of ship items. All in all props to being a PvP friendly place.
[Cassandra]: Poet will be unsurprised to learn that she has unread news.
Comments
When your ship is destroyed, it will drop all cargo it currently has and anyone can salvage that. Vast majority of players will return this to you, exceptions might be any PvP kills, which are extremely rare.
As far as ground theft is concerned, only the nanoseer comes close to being able to do this and even then, they can't steal your money.