This web page is running the v86 Javascript PC emulator which is simulating a complete PC computer with floppy and hard disks. Inside this simulated PC runs the x128 ZX Spectrum emulator which simulates a ZX Spectrum computer in which a BASIC program is loaded from a simulated tape and runs the simile of a gazing eye.
Inside each of these recursive emulation layers, the software doesn't know it is being simulated and at all times "believes" to be running on real, solid, physical hardware.
A study on the cascading emulation of computers as a "proxy" for emulated realities. A form of wondering: how real is this reality?