Why does Swiss Cheese have holes?!
Answers: Other cheeses don't.
Propionibacter shermani is one of the three types of bacteria used to make Swiss cheese, and it's responsible for the cheese's distinctive holes. Once P. shermani is added to the cheese mixture and warmed, bubbles of carbon dioxide form. These bubbles become holes in the final product. Cheesemakers can control the size of the holes by changing the acidity, temperature, and curing time of the mixture. Incidentally, those holes are technically called "eyes," and the proper Swiss name for the cheese is Emmentaler (also spelled Emmental or Emmenthaler).
From the gas that is given off by the bacteria as it hardens
They are not really holes, per se. When swiss cheese is made, air pockets form in the cheese. When the cheese is sliced, it goes over those pockets, causing holes in the slices.
when its made bubbles of gas and air are formed in the cheese and that makes the holes
because the culture they put in the cheese produces a gas which creates air bubbles and those bubble then pop creating the hole :)
in addition to peapop's answer: not only emmentaler has 'holes' but also a lot of other cheese we are producing here in switzerland.
I always thought that the fine Swiss people put the holes in, cuz that was where the calories were.
(We can only hope) ;)