Actually this option intends to be a more pedagogical than useful. However, it is true that it can be used to generate a cable which then will be analyzed or calculated, such as a Tyrolean (cable sloped by sliding a person hanging from it by a pulley), for example.
Pedagogical intent begins to show the difference between the forms that a cable acquires when it is subjected to loads perpendicular to the wire, as for example the wind (arc), parallel uniform loads, such as snow (parabola) or uniform loads along the cable, as for example the self weight (catenary).
You can see that for small sags on the rope, how the actual length of the cable practically does not change. On the other hand, if we increase the sag three possible forms are obviously different.