What is the difference between boiling and simmering food?

Boiling and simmering differ primarily in temperature and intensity. Boiling occurs at 212°F (100°C) at sea level, producing large, vigorous bubbles that roll and churn throughout the liquid. It's used for cooking pasta, blanching vegetables, or reducing liquids quickly. Simmering happens at a lower temperature, around 180–200°F (82–93°C), producing small, gentle bubbles that occasionally break the surface. Simmering is preferred for delicate tasks like cooking soups, stews, sauces, and braised meats, where prolonged gentle heat develops flavor without toughening proteins or breaking apart ingredients. Boiling meat, for example, can make it tough and dry, while simmering keeps it tender. Most recipes that say "bring to a boil, then reduce heat" are directing you to transition from boiling to simmering.