A teaspoon (tsp) is a common unit of measurement used in cooking and baking. It is typically used to measure small quantities of ingredients, such as spices, liquids, or baking powder. One teaspoon is equivalent to about 5 milliliters in volume. In recipes, teaspoons are often used alongside other measurements like tablespoons and cups. Understanding how to convert between these units can help ensure accurate ingredient proportions, which is essential for achieving the desired taste and texture in dishes.