Gallon (US)
The US gallon, symbol gal, equals 4 quarts, 8 pints, or 128 fluid ounces (~3.785 liters). Its origins trace to English wine and ale measures but were standardized in the US in the 19th century. Gallons are used for beverages, fuel, and large-volume recipes. While metric liters are the dominant unit of measurement in most countries, gallons remain widely used in the United States for everyday and industrial liquid measurements.
Teaspoon (US) (tsp)
The US teaspoon is a customary cooking unit equal to approximately 4.92892 milliliters. Its origin comes from traditional household spoons used for measuring spices and small quantities of liquid. The teaspoon has become a standard unit in American recipes, baking, and mixology, allowing for repeatable and accurate measurements. While small, it plays a critical role in precise culinary measurements and is often paired with tablespoons, cups, and other US volume units in recipes.