Who discovered calculus?

Calculus was not discovered all at once like one might find a hidden treasure chest. However, it was first widely explored by Isaac newton and a lesser known man by the name of Leibniz. They both had different views on the topic, but it's widely agreed that they are the two main "discoverers" of this field of math. Their work was also based off of centuries of exploration before their own birth, also. Newton's calculus was based more off of concrete mathematical fact, while Leibniz's ideas were more abstract and theoretical.