GeoGebra is a dynamic software. [br]In the following video you can see some examples of it:[br]You construct something using points, then you drag these points and the construction chnages as well.
Dynamic triangle: drag the points A and B to change the triangle
A line through 2 points: drag the points A and B to change it
Polynomials: drag the points A and B
Integrals: drag the points A and B to change the integration limits