The US cup is a volume unit equal to 8 US fluid ounces or approximately 0.2366 liters, the standard measurement in American recipes and cookbooks. When a recipe calls for 'one cup of flour' or 'half a cup of sugar,' it refers to this specific volume, not a drinking vessel of arbitrary size. One US cup equals exactly 236.588 milliliters.

The teaspoon (tsp) is the smallest standard cooking volume unit, equal to approximately 4.929 milliliters, found in recipes worldwide for measuring small quantities of spices, extracts, and medicine. It serves as the building block for larger measurements, with three teaspoons making one tablespoon. One US teaspoon equals exactly 1/6 of a US fluid ounce.