Fluid ounces are a unit of measurement used to quantify the volume of liquids. In the United States, one fluid ounce is equivalent to approximately 29.57 milliliters. This measurement is commonly used in cooking, beverage serving sizes, and nutrition labels to indicate how much liquid is contained in a product. In contrast, the UK fluid ounce is slightly different, measuring about 28.41 milliliters. Understanding fluid ounces is essential for accurate recipe preparation and portion control, especially when dealing with liquids like water, milk, or juice. Knowing how to convert fluid ounces to other volume measurements can also be helpful in various situations.