milk solids, processed milk product (like powdered or condensed milk) and/or milk fat
some kind of refined sweetener – usually a few different kinds like evaporated cane syrup, corn syrup, dextrose, etc.
yogurt culture (Lactobacillus bulgaricus and Streptococcus thermophilus are common cultures)
natural or artificial flavorings
natural or artificial coloring
sometimes trans fat
sometimes preservatives
stabilizers and thickeners like guar gum or carrageenan
other fillers like cellulose gum (a.k.a. the stuff made from wood pulp)