It was developed in the 17th century independently
by Sir Isaac Newton and G.W Leibniz. A branch of
mathematics that studies continuously changing quantities.
The calculus is characterized by the use of infinite
processes, involving passage to a Limit. The differential
calculus arises from the study of the rate at which
a function, usually symbolized by y or f(x), changes
relative to a change in the independent variable,
usually x.