How much is one cup?

The standard metric volume of one cup is approximately 240 milliliters (mL). However, the actual volume of a cup can vary depending on the context and measuring system being used. For example, in the United States, a standard cup measurement in cooking is 8 fluid ounces (fl oz), which is equivalent to approximately 236.6 mL. In the United Kingdom and many other countries, a standard cup is defined as 250 mL. It is important to specify the measuring system or standard when using the term "cup" to avoid confusion or errors in measurements.