PlayStation 4 differs from PlayStation 3 in that a Plus subscription is required to game online.
However, Plus, which costs £40 for 12 months, gives you much more than that.
Like on PS3, Instant Game Collection on PS4 gives those who subscribe to Plus free content. It's access to, in Sony's words, "a regular, curated selection of titles made exclusively available to PlayStation Plus members at no additional cost".
The PS4 games available on Instant Game Collection at the system's launch are Resogun and Contrast. More on Plus in December 2013 here.
Plus subs also get exclusive discounts on the PlayStation Store, and online game save. You can automatically or manually upload game save files to online game save storage, with up to 1GB of cloud storage allocated to your PS4 save files.
Other benefits include early access to exclusive game content, and automatic game patch downloads and installation.
Meanwhile, Sony outlined what features you can access without a PlayStation Plus membership.
You can access entertainment, film and TV services without Plus, but you'll need to subscribe separately to individual services.
You can also send gameplay video and screenshots to Facebook, and screenshots to Twitter, and livestream gameplay via Ustream or Twitch without a Plus sub.
You don't need a Plus sub to play PS4 games remotely using the Vita, either.
Also available without a Plus sub:
- Comparing Trophy data with other users.
- Sending and receiving text messages from other users.
- PlayStation Store access (users must pay to purchase premium content, obviously).
- Live item, activity feeds on Dynamic Menu.
- Party (cross game voice chat).
- Web browser.
- PlayStation App services (on iOS/Android devices).
- Certain titles built on a free-to-play model will not require PlayStation Plus for multiplayer functionality in North America. This list currently includes Blacklight Retribution, DC Universe Online, and War Frame in North America.