Binaural Recording   

Binaural recording techniques mimic human binaural hearing by effective stereo representation of interaural intensity and temporal differences between our two ears. 
The temporal differences occur naturally when a sound reaches the ears from one side of our head or the other. Depending on how much off-centre the sound source is there is a corresponding very short delay between the time it reaches the closer ear and when it reaches the further ear.  Likewise with interaural intensity differences. The sound reaching the closer ear will be of greater intensity than that reaching the farther ear which is in the sound shadow of the head. 
This effect is simulated for recording purposes by placing a stereo pair of microphones at a relative distance corresponding to the average distance between human ears.
A more sophisticated strategy involves using a model of the human head constructed of material with the same density and sound absorption characteristics. Small microphones are placed in the ears of the model. This technique simulates the finer temporal differences resulting from the complex shape of the pinnae of the ear resulting in more phase difference information. 
Recordings made using binaural techniques can be played back on loudspeakers but will only render their superior localization effects when listening on headphones.