PS5 Backwards Compatibility: Will Physical PS4 Game Discs Play on the ps5 game boost?

Yes, physical PS4 game discs will play on PS5. You'll be able to insert physical PS4 game discs into the PS5 and play them, as well as download digital software you've purchased from the PlayStation Store. Note that you won't be able to use physical game discs on the PS5 Digital Edition (See Also: PS5 Digital Edition vs PS5: What's the Difference?), as it doesn't have a disc drive.

PS5 Backwards Compatibility: Will PS4 Games Purchased from the PS Store Work on PS5?

The PS5 is backwards compatible with PS4 software, so this means both physical and digital software will work on the current-gen system. Assuming you’re using the same PSN account on PS5, you will have access to all of your PS4 purchases from the PlayStation Store. This includes PlayStation Plus titles – but you will have to ensure your subscription is active in order to play these.

PS5 Backwards Compatibility: Will PS4 Games Play Better on the ps5 game boost?

PS4 games will play better on ps5 game boost through the use of a "boost" mode, however this may cause compatibility issues and may not apply to every single game. You also might need to ensure that your PS4 games are installed to the PS5's SSD (See Also: PS5 SSD: Why It's Better Than HDD), although you will have the option to save space by using a more traditional external HDD (See Also: How to Use an External Hard Drive on ps5 game boost). Any games stored on the latter, of course, will not benefit from the speeds of Sony's super-fast SSD. For more information, check the following: Best PS5 and PS4 External Hard Drives and Which SSD Drives Will Be Compatible With PS5?

Here's what Sony has to say about PS4 games running better on ps5 game boost:
"We’re expecting backward compatible titles will run at a boosted frequency on PS5 so that they can benefit from higher or more stable frame rates and potentially higher resolutions. We’re currently evaluating games on a title-by-title basis to spot any issues that need adjustment from the original software developers." You can find out more about any potential improvements through the following link: PS5 Game Boost: All Major PS4 Game Improvements.