Vegetable stock is a flavorful liquid made by simmering various vegetables, herbs, and spices in water. Common ingredients include carrots, celery, onions, and garlic, which release their flavors into the water, creating a base for soups, stews, and sauces. This stock is often used as a vegetarian or vegan alternative to meat-based stocks, providing depth and richness to dishes without animal products. It can be made at home or purchased pre-made in stores, and it can be stored in the refrigerator or freezer for later use.