As the Laws were formulated in England, and were initially administered solely by the four British football associations within IFAB, the standard dimensions of a football pitch were originally expressed in imperial units. The Laws now express dimensions with approximate <answer>metric</answer> equivalents (followed by traditional units in brackets), though use of imperial units remains popular in English-speaking countries with a relatively recent history of <answer>metric</answer>ation (or only partial <answer>metric</answer>ation), such as Britain.
What unit of measurement is now expressed by the Laws?
metric