Employing binaural audio is a simple and effective way of creating very realistic sound, usually to be heard over headphones, of things that seem to be present in the space around you.
It is recorded with a dual microphone setup: microphones are placed in a dummy head, or clipped onto the side of someone's actual head. They pick up what your ears would be hearing including the architecture of a human head (ie, if the left-ear microphone records something to the right, the fact of a head being in the way is included in the recording, and vice versa) so that when you put on headphones, the effect is precisely recreated.
When you record something in a location with a specific acoustic, and listen back to it in the same or similar place, it can sometimes be hard to believe what you are hearing is not taking place for real, around you. Depending on the kind of headphone being used, it’s also possible to build upon or modify the real space around you, rather than simply replace it.
The famous ‘virtual barber shop’ is an example of a simple binaural recording (wear headphones): https://www.youtube.com/watch?v=IUDTlvagjJA