The main ingredient used to make pasta is durum wheat semolina or flour mixed with water. Durum wheat, being high in protein and gluten, gives pasta its firm texture and allows it to hold its shape when cooked. The mixture is kneaded into a dough, then shaped into various forms such as spaghetti, penne, or fettuccine. Pasta can also be made from other types of flour, including whole wheat or gluten-free alternatives, but durum wheat remains the most traditional and widely used ingredient in Italian pasta-making.