Calculus
The word calculus comes from a Latin word that means “pebbles”.
One of the earliest methods of calculation was the manipulation of piles
of pebbles. The Roman abacus (or “calculator”) made us of pebbles
instead of beads. Physicians use the word calculus to mean unwelcome
stone-likes substances in the body such as kidney stones and gallstones.
The dentists clean calculus off their patient’s teeth.
In modern mathematics, calculus is the mathematical tool that is
used to study how things change and the rate at which they change.
Change is one thing we encounter all the times of the day. Our moods
change so do the prices of commodities, the salaries, the temperature
and the time of the day. Motion of bodies brings about change. In such
a situation, it is but natural to ask questions about the rate at which
things change. In discussing such questions, calculus gives the language
and techniques we need to focus on change. Calculus is the mathematics
of change.