A P8.PNG file contains a PICO-8 game, which is an 8-bit retro-style game that can be played with the PICO-8 virtual fantasy gaming console. It stores a game in a proprietary binary format similar to the .PNG format. P8.PNG files include compiled PICO-8 source code and sprites, sound effects, maps, and music data featured in the game.

You will most likely only encounter a P8.PNG file when trying to play a PICO-8 game downloaded from the Internet or shared by another PICO-8 gamer. The files are compiled from .P8 PICO-8 source code files using the PICO-8 application. P8.PNG files can be opened and played with the PICO-8 application. The program can export a game as an .HTML and .JS file to be embedded and playable in a website or as a .BIN file to be played in Windows, macOS, and Linux. P8.PNG files may also be opened with programs that support PNG files. However, the programs will not be able to play the game, they will only be able to view the PNG image of the game cartridge. PICO-8 is a cross-platform program that allows you to create, play, and share tiny retro-style games. The games can be saved as "virtual cartridges" with .p8 or .p8.png file extensions. P8 files are saved in text format and are used to store source code for games that are still in development. And as previously mentioned, P8.PNG files are saved in a binary format that can be played with PICO-8.