PS2 Backward Compatibility: PS1 Yes, PS3 No

PS2 plays PS1 games but cannot play PS3 games.

Why PS1 Works

• Built-in PS1 emulator allows PS2 to run PS1 discs and save data.

Why PS3 Doesn't Work

• PS3 uses completely different architecture (Cell processor, different OS).
• PS2 hardware cannot run PS3 games.

Note on "PS1 Classics" on PS2 Discs

Some PS2 games include bonus PS1 games on the same disc, but these only work within the PS2 game—not as standalone PS1 titles.