What technique does this site use?
It's called by (at least) three names: The Method of Loci, Memory Palaces, and The Art of Memory. Loci refers to a particular point or place. It goes back at least as far as Cicero, who used it to memorize speeches to the Roman senate.
How does it work?
This site follows the idea quite closely. You first form a visual image that illustrates what you want to remember, place the visual image in a building, and then picture yourself walking through that building.
Is there any research to support this technique?
Plenty; too much to list here. Many competitive memory contestants use the technique successfully. Joshua Foer's book Moonwalking with Einstein (2011) is a great introduction. Also of interest is the research on place cells, grid cells, and head-direction cells in the field of neuroscience.
How does this app use artificial intelligence?
This app uses uses the AI image generator DALL-E 2 to create images based on the description you enter.