The primary ingredient in traditional tzatziki sauce is yogurt, specifically strained Greek yogurt. This ingredient provides a creamy texture and tangy flavor that is characteristic of tzatziki. Other common ingredients include cucumber, garlic, olive oil, vinegar, and fresh herbs such as dill or mint. Tzatziki is often served as a dip, sauce, or condiment and is popular in Mediterranean and Middle Eastern cuisines, particularly in Greek dishes like souvlaki and gyros. The yogurt not only contributes to the flavor but also adds a probiotic element, making it a healthy choice.