Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

So I am wondering about how CD games and the PSN interact.

I got Horizon: Zero Dawn on Friday on disc.
Played the crap out of it and really enjoy it.

Decided to get the DLC on the PSN store.
It downloaded.

But how does it interact with my disc game?

Will I need to restart to take advantage of the new content?

I don't do much on PS4....primarily a Steam/PC player...so this is kind of different for me.

If by "restart", you mean start a completely new game, then no, you shouldn't need to do that.

As for the interactions...

When you buy a game disc these days, pretty much the entire game is installed on your console's hard drive. The disc means that there's less to download before you start playing the game (because a lot of it is copied off of the disc). And you have the option to pass the game along to someone else later on so that they can play it instead of you. The upshot of this is that the DLC expansion doesn't really care whether you're running the game with the disc, or downloaded it onto your console. The DLC will work just fine either way.