Differentiation is a process in calculus that involves finding the instantaneous rate of change of a function based on one of its variables. It is the process of determining the derivative of a function at any point. The derivative of a function at a point is the slope of the line tangent to the curve at that point. The derivative of a function is denoted by $\frac{dy}{dx}$ or $y$ . The derivative of a function $y=f(x)$ is defined by the limit: $$\frac{dy}{dx}=\lim_{h\to 0}\left. However, in practice, it is often more convenient to use standard derivatives in conjunction with rules such as the chain rule, product rule, and quotient rule. Differentiation can be used to find the rate of change of one quantity with respect to another, such as acceleration, or to calculate the highest and lowest point of a curve in a graph.