Imperial pint (pt)
Definition: An imperial pint is one eighth of an imperial gallon, equal to about 568.261 milliliters.
History/origin: The imperial pint became one of the best-known British imperial volume units after formal standardization in 1824.
Current use: Imperial pints are still well known in the UK, especially for beer, cider, and some milk sales.
Cubic kilometer (km³)
Definition: The cubic kilometer is a huge metric volume unit. A 1 km by 1 km by 1 km cube contains 1,000,000,000 m³, or 1,000,000,000,000 L.
History/origin: Earth science needed a readable unit for massive natural volumes, so km³ became useful for water bodies, ice, rock, magma, and atmosphere-scale quantities.
Current use: Km³ appears in hydrology, climate reports, ocean volume estimates, glacier studies, volcanic eruption data, reservoir capacity, and large-scale geography.