CHIP-8 is a video game console from the '70s. Except no physical CHIP-8 machines were actually made -- CHIP-8 is a virtual machine, designed to be simulated by existing physical machines.
This is a CHIP-8 emulator, which can run programs written for CHIP-8.
To try it out, install Rust, and run:
$ cargo run --release < games/snake.ch8
The controls for the snake game are WASD for up/left/down/right.
For more information on CHIP-8, check out the Wikipedia article. There's also a nice technical reference.