Because pebbles were used as counters in Roman counting-board abacuses, Romans called their reckoning "placing pebbles" (calculos ponere), and would settle accounts by "calling someone to the pebbles" (vocare aliquem ad calculos); the Latin word calculare appeared around 400 AD in Spain. The word calculate was used in English in this sense at least as early as 1672, several years before the publications of Leibniz and Newton, who wrote their mathematical texts in Latin.

In addition to differential calculus