how is yogurt made?
Yogurt is made from heating milk, and before milk can be made into yogurt the whey has to be removed from it.  You add a certain bacteria to it, and then it starts to coagulate into yogurt.  The bacteria that are added to the milk to turn it to yogurt at Lactobacillus bulgaricus and Streptococcus thermophilus.  After the yogurt is made sugar may be added to make it a specific flavor like chocolate or vanilla.