Key lime juice is the juice extracted from Key limes, a small, round variety of lime known for its tart flavor and aromatic qualities. These limes are typically smaller and have a thinner skin compared to regular limes. The juice is a key ingredient in many recipes, most famously in Key lime pie, a popular dessert in the United States. Rich in vitamin C, Key lime juice is often used in beverages, marinades, and dressings. Its bright, tangy flavor enhances both sweet and savory dishes, making it a versatile ingredient in various cuisines.