HAL 9000 Screensaver is a tribute to the film 2001: A Space Odyssey in which there was a computer installed in the spacecraft. This device is represented on this screen saver.
Specifically, HAL 9000 Screensaver reproduces the graphic elements that appeared in the computer, which was capable of dealing with infinite data in a few seconds given its very high power, which made it a key element of the spacecraft in which it was present.
The realism of the screen saver makes you think you're in front of the supercomputer that caused a furor in the film directed by Stanley Kubrick. Its aspect ratio is totally adapted to that of your own monitor.