Integral can refer to one of several closely related concepts from calculus. The integral is represented by the integral sign " ∫ ", it actually is an S that means integration, and stands for summation " Σ ".

• The indefinite integral, which is a family of functions formed by adding an arbitrary constant to an antiderivative.
• The definite integral, which gives the area under a curve between two points.
• The line integral, an integral under a curve, taken over a scalar or a vector field.
• The flux integral, which measures the amount of flow through a given surface in a vector field.