Grappling hooks — both thrown and shot out of some kind of gun — are probably the most ubiquitous piece of technology in comic books today. Shoot the rope up, wait until the hook catches a ledge, and, presto, an easy ride up a tall building. Shooting a grappling hook into the air isn’t a problem; making sure it can actually latch onto something and then pull you up with sufficient force is. Superheroes really push the boundaries of believability when they shoot grappling hooks up while falling off a building. In comic books, they then swing to safety, while in real life (as PopSci notes) the force exerted on someone who hits the ground and someone who stops just short of the ground is basically the same — meaning you’d have one dead superhero.