You don't "need" paracord in your prepping supplies, but it would be foolish to not include it.
Not only is it exceptionally strong for its weight, you can strip it into its components to further its uses.
Inside your typical 550 cord are several smaller strands that can be used for various small lashing projects, first aid uses (splints and such), sewing, snares, and even as impromptu fishing line.
Paracord (from a reputable manufacturer of Mil. Spec. cord) is better suited to many survival uses than traditional ropes and twines particularly for its durability. When you pull many types of rope to put tension on them, they tent to stretch over time, making the original knots loose. Paracord generally doesn't do this.
If I had to choose between Paracord and a general purpose stranded rope for my prepping, I would pick Paracord. But, since I don't have to choose, I have some of both in my kits.
Everything he said ^ is great. You can use the internal strands to tie together brush or whatever to make a shelter even. Trip wire, fishing line, pretty much anything you can think of. Hanging a deer from a tree lol. I prefer paracord because it doesn't stretch over time as well.