The metric system is used as the basis for all hollow measures that are valid worldwide today (Table 1); see also under Dimensions. In addition, very old gauges are still in use (Table 2). The Anglo-American measurement systems are almost only used in the USA, England and some other countries (Table 3). The ancient Roman hollow measures are included under Congius. In the sources on ancient units of measurement, the information on volumes often varies and the differences are sometimes considerable. See also other measurement-related lists under the keywords barrel types, area measures, bottles, units of measurement, area under vines, wine vessels and wine production quantities.