What does calculus mean?
The word arithmetic ultimately derives from the Greek noun arithmos, meaning "number," with stops along the way in Latin, Anglo-French, and Middle English. Algebra is a form of arithmetic in which abstract entities, usually represented by letters, are used in place of numbers. A 9th century Persian mathematician named Muhammad ibn Musa al-Khwarizmi is credited with establishing the basis for modern algebraic theory though his book Kitab al- jabr wa'l-muqabalah ("Book of Restoring and Balancing"). It is from the al-jabr (also translated as "the reduction") in the book's title that our word algebra derives. (In Arabic, al- functions as a definite article comparable to "the.") Geometry derives from the Greek words for "earth" and "measure," while trigonometry derives from words for "triangle" (trigōnon) and "measure." Calculus is an advanced category of mathematics concerned with the calculation of a rate that changes continuously (known as a derivative), such as the arc of a curve or the speed of a falling object. Isaac Newton and Gottfried Leibniz are both credited with the invention of modern calculus in the 17th century. In Latin, calculus means “pebble.” Because the Romans used pebbles to do addition and subtraction on a counting board, the word became associated with computation. Calculus has also been borrowed into English as a medical term that refers to masses of hard matter in the body, such as kidney stones.
