|This article/section deals with mathematical concepts appropriate for a student in late high school or early university.|
The length can be approximated by selecting a finite number of points along the curve and connecting the points with straight lines. The sum of the line segments can give a lower estimate for the length of the arc. The more points used, the closer the approximation to the curve. Technically, the arclength is the supremum of all such sums, represented as an integral.