Another group of people who like Phonetics are the International Phonetics Association (IPA)... Yes, it really does exist... and they have listed all the possible sounds that a normal mouth can make, and which are in "contrastive distribution in at least one language". Well, let's not worry about that, but what they have done for us is put them into a lovely chart - although it may look very complicated, it is actually rather exciting for people like me.
The list of sounds is exhaustive and contains such spectacular sounds as /ʘ/ /ǃ/ /ɓ/, and it even contains some sounds that I cannot demonstrate here because, well let's just say, they are beyond my articulation spectrum. One of these sounds my German friends will definitely know about because it is that /r/ sound at the back of the mouth, which is incredibly difficult to do, especially for me.
Let's just pause here for a moment and think isn't it wonderful that all of these sounds actually exist in languages across the world? ... No?
Then imagine trying to teaching these sounds to a group of students - the class will soon enough become hysterically tongue-tied and will never forget the moment you tried to teach them some of these weird and wonderful sounds. Isn't that interesting? ... No?
Then what about this video? [plays video, see below]
Now if I change the image but not the sound, what do you hear? [plays different video with same audio, see below]
I guess that for the first video you heard 'bar' and for the second you heard 'far', is that right? But honestly, the sound of the video did not change at all. It kind of makes us think that vision is more important than hearing, even in spoken English. Now you can rewind and replay this video for eternity and even though you now know what happens in the videos, you can still listen and the effect will not change. Now you cannot deny that that is not interesting!