The primary ingredient in yogurt is milk. Yogurt is made by fermenting milk with specific bacterial cultures, which convert lactose, the sugar found in milk, into lactic acid. This fermentation process not only thickens the milk but also gives yogurt its distinctive tangy flavor and creamy texture. Different types of milk, including cow, goat, or sheep's milk, can be used, and the resulting yogurt can range from plain to flavored varieties. Yogurt is a popular dairy product enjoyed worldwide for its taste, versatility in recipes, and nutritional benefits, including probiotics that support gut health.